A trailer’s handling task can finish while the trailer still occupies the bay. If the next part of the system cannot receive it, the bay remains unavailable to the next visit. A dashboard that records only active service time can therefore report spare capacity while the physical resource is still occupied.
The short answer is to record service completion and resource release as separate events. In a finite-buffer model, a completed unit can block the upstream resource until a downstream place becomes available. Adding a holding position may change where units wait without changing their final departure times. The benefit and the remaining bottleneck need different measures.
This article develops original deterministic card-and-timeline examples. All visits, capacities and minutes are fictional. It supplies no vehicle-movement, parking, traffic-control or release procedure. Begin with the Yard Management subject guide for the complete operational and information context. Here the narrower learning task is to reconstruct how a physical place remains occupied after its active work has ended.
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Track which resource a unit occupies after its active work ends, then test the downstream constraint.
ROUTE 2 · CHAPTERS 7–12
Compare waiting and holding
Balance the time account as holding capacity changes.
ROUTE 3 · CHAPTERS 13–18
Check occupancy and reporting
Separate available resource time from completed visits.
ROUTE 4 · CHAPTERS 19–24
Change and test the model
Inspect source context and solve a changed timeline.
ROUTE 5 · CHAPTERS 25–29
Check evidence and transfer
Verify the new account and choose the responsible next route.
Chapter contents
Define the unit and state events · Chapters 1–6
1. Separate the task, the unit and the resource
2. Define the paper network before calculating
3. Identify the four timestamps needed for each unit
4. Follow the first unit without skipping its completed state
Compare waiting and holding · Chapters 7–12
7. Calculate queueing, service and blocking separately
8. Distinguish active utilisation from occupied time
9. Introduce an unlimited holding model as a comparison
10. Check how much holding the comparison actually requires
Check occupancy and reporting · Chapters 13–18
13. Compare all three bay occupancy histories
14. Avoid adding a holding place only on the screen
15. Preserve the endpoint convention at simultaneous events
16. Keep finite-run throughput separate from a service-rate claim
Change and test the model · Chapters 19–24
19. Change service time without assuming the receiver changed
20. Change the downstream opportunities as a separate experiment
21. Understand the limits of the deterministic card model
22. Connect the model with primary blocking research
Check evidence and transfer · Chapters 25–29
25. Check the changed timeline and its limitations
26. Build a record that distinguishes the physical states
27. Repair, stabilise and extend the learner's route
CHAPTER 1 OF 29 · Define the unit and state events
1. Separate the task, the unit and the resource
A handling task is an activity. A trailer or other handling unit is an entity. A bay is a resource that can remain occupied by that entity before, during and after the activity. These three descriptions are connected but should not be represented by one ambiguous completed flag.
In our model, service completion says that the stipulated processing time has elapsed. Bay release says that the unit has left the bay for its next permitted model state. Neither event by itself means that an actual site has authorised a movement or completed every responsibility associated with a visit.
This separation makes a capacity question answerable. If the next unit needs the same bay, the relevant constraint is when that bay becomes available, rather than only when the previous processing task finishes. A record can preserve both events without declaring either redundant. Each supports a different question about work, waiting and the next feasible start.
CHAPTER 2 OF 29 · Define the unit and state events
2. Define the paper network before calculating
Use one bay with capacity for one unit, followed by a downstream receiver. A unit requires three minutes of active bay service. The receiver accepts at most one unit at each of the fixed times 5, 10, 15 and 20 minutes. These are abstract acceptance opportunities, not an operating timetable for a real gate.
Four units, A through D, arrive at times 0, 2, 4 and 6 minutes. They are served in that order. Initially the system is empty. Transfer between model states takes zero time, and if service finishes exactly at an acceptance opportunity, the unit may use that opportunity. We state this endpoint convention because another convention could change the event sequence.
First assume there is no holding position between bay and receiver. A unit stays on the bay after service until the receiver accepts it. That is the blocking rule. It differs from a model that automatically creates unlimited space for completed work whenever a processing timer reaches zero.
CHAPTER 3 OF 29 · Define the unit and state events
3. Identify the four timestamps needed for each unit
For each unit i, record arrival a_i, bay-service start s_i, service completion c_i and bay release r_i. With a three-minute service requirement, c_i = s_i + 3. Under the no-holding rule, release occurs at the first available receiver opportunity at or after c_i.
The next unit can start only when it has arrived and the previous unit has released the bay. Thus s_i = max(a_i, r_(i−1)), with the initial bay available at time zero. This recurrence carries the physical occupancy constraint forward through the sequence.
The formula is deliberately small. It does not account for different bay compatibility, handling teams, travel time or discretionary release decisions. Those would require additional states and assumptions. Its value is that every start is justified by an arrival and a released resource, so a reader can identify exactly where the common shortcut of using the previous service-completion time would change the model.
CHAPTER 4 OF 29 · Define the unit and state events
4. Follow the first unit without skipping its completed state
Unit A arrives at time zero and starts immediately. Its active service finishes at minute 3. The next receiver opportunity is minute 5, so A remains on the bay for two additional minutes and releases it at 5.
During the interval from 3 to 5, A is completed with respect to its processing task but still occupies the bay. There is no contradiction. Completion and release describe different state transitions. A model that assigns both events to minute 3 has silently added another destination or changed the downstream rule.
This two-minute interval is blocked bay time in the paper model. It is not active service, and it is not pre-service queueing for A. Giving it a separate label helps explain why an apparently idle bay resource cannot yet serve B. Before calling such time avoidable in a real site, one would need the relevant physical, safety and authorisation context, which this exercise does not provide.
CHAPTER 5 OF 29 · Define the unit and state events
5. Let the blocked resource change the second start
Unit B arrives at minute 2. It cannot start then because A occupies the bay, and it cannot start at minute 3 merely because A’s service finished. The bay releases at minute 5, so B starts at 5 and finishes service at 8.
The minute-5 receiver opportunity has already been used by A. B’s next opportunity is minute 10, giving another two minutes of blocked bay time. B’s pre-service wait is 5 − 2 = three minutes, while its total arrival-to-receiver interval is 10 − 2 = eight minutes.
Those two waits have different causes and positions. The first belongs to B before its bay service; the second belongs to B after service while it still holds the bay. Adding them may be useful for a total, but keeping them separate is essential for understanding which resource remains occupied and how the delay affects later units. One visit’s blocked interval becomes another visit’s delayed start through the release recurrence.
CHAPTER 6 OF 29 · Define the unit and state events
6. Reconstruct the complete no-holding timeline
Apply the same rule to C and D. C starts at 10, finishes at 13 and releases at 15. D starts at 15, finishes at 18 and releases at 20. Each unit uses three minutes of service and two minutes of post-service bay occupancy.
| Unit | Arrival | Service start | Service complete | Bay release and receiver acceptance |
|---|---|---|---|---|
| A | 0 | 0 | 3 | 5 |
| B | 2 | 5 | 8 | 10 |
| C | 4 | 10 | 13 | 15 |
| D | 6 | 15 | 18 | 20 |
The table is an original fully specified event account. Read across one row to follow a unit, then down the release and start columns to follow the bay. Those two readings check different relationships.
The bay is continuously occupied from 0 to 20. Active service occupies twelve minutes in total; blocked completed units occupy the remaining eight. Describing the resource as used for only twelve minutes would omit physical occupancy that the next visit cannot use under the stated rules.
CHAPTER 7 OF 29 · Compare waiting and holding
7. Calculate queueing, service and blocking separately
Pre-service waits are 0, 3, 6 and 9 minutes, totalling eighteen. Active service totals twelve minutes. Post-service bay blocking totals eight. Adding these categories gives 38 unit-minutes of time in the complete system before receiver acceptance.
Independently, arrival-to-receiver durations are 5, 8, 11 and 14 minutes, also totalling 38. The agreement checks the partition. A missing blocked interval would break it even if the final departure times in the table happened to be correct.
A unit-minute is one unit present for one minute. It is different from a clock minute of bay occupancy when several units can wait elsewhere at the same time. The bay contributes at most one occupied place at a time, while the external queue can contain several units. This distinction helps readers compare an area-under-a-count curve with the durations accumulated separately for each unit.
CHAPTER 8 OF 29 · Compare waiting and holding
8. Distinguish active utilisation from occupied time
Over the declared 20-minute horizon, active service uses 12/20 = 60% of the bay’s clock time. Physical occupancy uses 20/20 = 100%. Both percentages are correct under their definitions. Neither should be relabelled simply as utilisation without explaining which state was counted.
The remaining 40% is not available capacity in the no-holding model. Completed units are using the bay while waiting for downstream acceptance. A planner who books another visit into those intervals has changed the occupancy constraint, rather than discovered time that the original schedule overlooked.
This is a useful interpretation check for performance reports. A high activity measure and a high occupancy measure answer different questions, and a low activity percentage need not identify the cause of lost capacity. The next useful observation is the state occupying the resource when active work is absent. A numerical summary becomes actionable only after the state and its responsible process are understood.
CHAPTER 9 OF 29 · Compare waiting and holding
9. Introduce an unlimited holding model as a comparison
Now change one assumption: allow completed units to leave the bay immediately for an ideal unlimited holding area. Keep arrival times, service durations, service order and receiver opportunities unchanged. The holding area is a mathematical comparison, not a claim that any real yard has unlimited suitable space.
A starts at 0, completes at 3 and releases the bay at 3. B can then start at max(2,3) = 3 and complete at 6. C starts at 6 and completes at 9. D starts at 9 and completes at 12. Their bay-release times are now 3, 6, 9 and 12.
The receiver still accepts them at 5, 10, 15 and 20. No additional opportunity was created. This immediately suggests an important distinction: freeing the bay earlier can reduce some waits and change the resource account while leaving the final receiver sequence unchanged. The comparison needs both outcomes to remain visible.
CHAPTER 10 OF 29 · Compare waiting and holding
10. Check how much holding the comparison actually requires
In the unlimited-holding calculation, A waits off-bay on [3,5), B on [6,10), C on [9,15) and D on [12,20). We use half-open intervals so an acceptance at an endpoint frees a place at that time.
Two units are present in holding during [9,10), when B and C overlap, and during [12,15), when C and D overlap. The maximum holding count is therefore two. Calling the comparison feasible with only one holding place would ignore the overlap even though each unit individually has a plausible waiting interval.
This is a capacity check distinct from summing waiting durations. The total holding time is 2 + 4 + 6 + 8 = twenty unit-minutes, but twenty unit-minutes does not mean twenty places are needed. The maximum simultaneous count determines this simple space constraint. Duration sums and peak occupancy describe different aspects of the same set of intervals.
CHAPTER 11 OF 29 · Compare waiting and holding
11. Add exactly one holding position
Replace the unlimited area with one holding position. A leaves the bay at 3 and uses holding until receiver acceptance at 5. B begins service at 3, completes at 6 and enters holding because A has already left. B occupies that position until 10.
C begins service at 6 and completes at 9. Holding is still occupied by B, so C cannot leave the bay at 9. It waits there until 10, then transfers into the newly free holding position. C remains in holding until receiver acceptance at 15.
D starts at 10, completes at 13 and waits on the bay until 15 because C occupies holding. It then waits in holding until 20. The bay-release times are 3, 6, 10 and 15. This model has eliminated some blocking, but not all of it. The single holding place has a finite occupancy history that must be honoured by every transfer.
CHAPTER 12 OF 29 · Compare waiting and holding
12. Reconcile the one-position account independently
Pre-service waits are now 0, 1, 2 and 4 minutes, totalling seven. Service still totals twelve. Blocked bay waits are zero, zero, one and two minutes, totalling three. Holding waits are two, four, five and five minutes, totalling sixteen.
The complete account is 7 + 12 + 3 + 16 = 38 unit-minutes. That matches the original total arrival-to-receiver time because the receiver acceptance times and arrivals remained unchanged. Waiting has moved between states, while some upstream waiting has also been redistributed.
This is not a claim that adding storage never improves a system. It is a statement about the specific deterministic comparison. Here the fixed receiver sequence leaves the total visit durations unchanged. The bay becomes available earlier, which could matter for another task or a changed arrival stream, but that benefit should be reported as such rather than converted automatically into faster completion of these four visits.
CHAPTER 13 OF 29 · Check occupancy and reporting
13. Compare all three bay occupancy histories
With no holding, the bay is occupied for twenty minutes: twelve in service and eight blocked. With one holding place, it is occupied for fifteen minutes: twelve in service and three blocked. With enough holding for the calculated overlaps, it is occupied for twelve minutes, all active service.
Receiver acceptance remains at minutes 5, 10, 15 and 20 in every case. The final unit therefore leaves the model at minute 20 regardless of the holding comparison. This pair of statements is the central result: a resource can be freed sooner without the overall completion time improving under an unchanged downstream constraint.
A report should state which benefit was observed. Reduced bay occupancy, reduced pre-service waiting, increased holding use and unchanged receiver completion are different findings. They can all be true at once. Combining them into a single claim that the yard became faster would leave the reader guessing which part of the service actually changed.
CHAPTER 14 OF 29 · Check occupancy and reporting
14. Avoid adding a holding place only on the screen
The finite-buffer comparison depends on an actual permitted model state with a declared capacity. Changing a digital label from in service to complete does not create that state. If the physical unit still occupies the bay, the bay remains occupied regardless of the dashboard colour.
A real holding arrangement also involves suitability, authorised movement, safety and other site conditions. This article supplies none of those operating decisions. The mathematical model only makes clear that a claimed additional capacity needs a corresponding resource and valid transfer relationship, rather than a bookkeeping convention that moves an entity into an undefined location.
The Yard Management root develops the wider distinction between planned and confirmed physical states. Connect that principle to this numerical example: an availability calculation should use the event that genuinely releases the resource. If its evidence is missing, the state remains unresolved instead of becoming free merely because another task has ended.
CHAPTER 15 OF 29 · Check occupancy and reporting
15. Preserve the endpoint convention at simultaneous events
At minute 10 in the one-position model, B is accepted by the receiver, C leaves the bay for holding and D starts bay service. Our zero-transfer-time convention permits those state changes at the same clock time in that dependency order. The holding position is not occupied by B and C simultaneously over a positive interval.
If transfer or preparation required a positive duration, it would need to be included explicitly. Treating a real transfer as instantaneous because a paper example did so would change the practical interpretation. Conversely, counting both endpoint occupants as two simultaneous places would contradict the half-open interval convention used in the model.
Write the event rule beside the timeline. This lets another learner reproduce the same sequence and identify why a different convention produces another answer. A scheduling calculation is stronger when its boundary rules are explicit, rather than relying on software to choose an event order that the reader never sees.
CHAPTER 16 OF 29 · Check occupancy and reporting
16. Keep finite-run throughput separate from a service-rate claim
Four receiver acceptances occur over the 20-minute observation horizon, giving a finite-run completion count of four and an average of 0.2 units per minute over that chosen horizon. The bay’s active processing rate while continuously working is one unit per three minutes. These are different quantities.
Neither number alone establishes a long-run stochastic capacity or an actual site’s achievable performance. Initial emptiness, finite arrivals and fixed receiver opportunities are part of the example. A different observation window could produce another count-per-time summary without changing the processing duration of a single task.
The useful comparison retains the complete sequence. The holding variants change the bay’s release history, while the selected receiver bottleneck remains fixed. If a report uses a rate to claim improvement, ask which events were counted, over which horizon and under which initial conditions. That question prevents a change in measurement boundary from masquerading as a change in physical service.
CHAPTER 17 OF 29 · Check occupancy and reporting
17. Check the area under the number-present curve
Let N(t) be the number of these four units present in the complete model after arrival and before receiver acceptance. Each unit contributes one to that count over its own arrival-to-acceptance interval. Integrating N(t) over the horizon therefore gives the sum of those four durations, 38 unit-minutes.
Dividing by twenty minutes gives an average number present of 1.9 over the complete horizon. The mean duration of the four completed visits is 38/4 = 9.5 minutes. Multiplying 4/20 by 9.5 again gives 1.9. This is a finite-run accounting identity here because every included unit arrives and completes within the declared horizon.
Do not silently apply the same arithmetic to a cropped record with units already present at its start or unfinished at its end. Their partially observed intervals need an appropriate boundary account. The identity checks this complete empty-to-empty example; it is not evidence that every dashboard average can be multiplied without examining its population and observation window.
CHAPTER 18 OF 29 · Check occupancy and reporting
18. Crop the record to expose a boundary problem
Suppose the report stops at minute 12 in the original no-holding model. A and B have been accepted, while C and D remain within the system. Averaging only A and B’s completed durations gives 6.5 minutes, but that summary omits the unfinished visits’ ongoing time.
It would be incorrect to combine that completed-only mean with all four arrivals and expect to reconstruct the average number present over the cropped horizon. The numerator, population and observation boundary no longer describe the complete set of intervals used by the earlier identity.
This example adds no new queueing mechanism. It tests the evidence record. A correct event simulation can still be summarised misleadingly if unfinished units disappear from the report. State whether a duration measure concerns completed visits, all units present or another defined population. A useful capacity analysis needs the right events and an honest reporting boundary, not merely a more elaborate mathematical model.
CHAPTER 19 OF 29 · Change and test the model
19. Change service time without assuming the receiver changed
Shorten the fictional bay service from three minutes to two while retaining no holding and the original arrivals and receiver opportunities. A finishes at 2 but cannot release until 5. B then finishes at 7 and releases at 10, followed by C at 12 and 15, and D at 17 and 20.
The receiver acceptance sequence is unchanged. Active service totals eight minutes, while bay blocking grows to twelve. The bay remains occupied for the same twenty minutes. Faster active processing alone did not create another receiver opportunity or remove the no-holding constraint.
This controlled change does not mean faster equipment is never valuable. It identifies why a proposed improvement should be tested against the complete state sequence. In this example, the saved service time becomes additional completed-but-blocked time. A resource-focused report would miss that substitution if it measured only the processing timer and assumed every minute saved there must also be saved at final departure.
CHAPTER 20 OF 29 · Change and test the model
20. Change the downstream opportunities as a separate experiment
Return to three-minute bay service but let the receiver accept one unit at each of minutes 4, 8, 12 and 16. With no holding, the bay starts are 0, 4, 8 and 12; service finishes at 3, 7, 11 and 15; release follows at 4, 8, 12 and 16.
Now the final completion changes because the downstream schedule changed. Bay blocking totals four minutes rather than eight, while active service remains twelve. The comparison isolates another mechanism from the holding-place experiment. It should not be presented as evidence that extra storage caused the faster completion.
A useful improvement study changes or records the relevant factors clearly enough to explain which one produced the observed result. Changing arrivals, service times, holding capacity and receiver availability together might improve a real service, but it makes a simple causal explanation harder. In the classroom, changing one assumption at a time makes the dependency visible before several factors are combined.
CHAPTER 21 OF 29 · Change and test the model
21. Understand the limits of the deterministic card model
Every duration and acceptance opportunity in our example is known exactly. Real visits can vary, and resources can fail, become unsuitable or be delayed by work omitted from this small model. A deterministic timeline is useful for explaining one blocking mechanism without supplying a complete operational forecast.
The source of uncertainty matters. Variability in service, uncertainty in arrivals and uncertain downstream availability can affect the sequence differently. Replacing them all by average durations may conceal interactions between completed work and a full buffer. The present examples establish that the state constraints matter even before uncertainty is added.
Use the model to ask a sharper question of actual evidence: when did active work end, what resource remained occupied, which downstream condition prevented release and when was that condition resolved? Those observations can motivate a more suitable analysis. They do not authorise a physical workaround or prove that any one operational change is appropriate for an actual site.
CHAPTER 22 OF 29 · Change and test the model
22. Connect the model with primary blocking research
Bierbooms, Adan and van Vuuren’s research on finite-buffer tandem queues studies a blocking-after-service model in which completed work can prevent the upstream server from starting another job. Its treatment is more general and probabilistic than our deterministic card example.
The research was first published online on 16 November 2011 and appears in the 2013 journal volume. The live research page was checked on 26 October 2026. We use it for the formal queueing context; none of the four visits, receiver times, occupancy totals or comparison results here is reported experimental data from that paper.
The source helps name the mechanism without making the paper a yard operating manual. Our application remains a deliberately small educational model. Reading the original research is an extension route into finite buffers and dependent service effects, while actual logistics decisions still require evidence and competent arrangements for the specific physical system.
CHAPTER 23 OF 29 · Change and test the model
23. Relate blocking to the existing yard lessons
The arrival-clustering lesson examines how arrivals and service interact to build and clear a queue. The unbroken-bay-time lesson examines whether a continuous visit fits within a bay’s available calendar.
This article adds a different dependency: a visit’s release time is affected by the downstream state after its own service has finished. A static service duration is therefore not automatically its full occupancy interval. Once the release behaviour has been defined, the calendar and arrival lessons can use the appropriate intervals without being asked to infer the missing state transition themselves.
Keep the questions distinct when choosing the next reading route. Is the unresolved issue an arrival pattern, a fragmented calendar or a unit that cannot leave its current resource? They can occur together in a real system, but separating them first makes the combined problem easier to explain and less likely to be simplified through the wrong shortcut.
CHAPTER 24 OF 29 · Change and test the model
24. Try a changed-context three-unit problem
A new paper model has one bay, no holding and three units arriving at times 0, 1 and 2. Each needs two minutes of active service. The receiver accepts one unit at each of minutes 4, 7 and 10. Preserve the same endpoint convention and service order.
Calculate each service start, completion and bay release. Then total pre-service waiting, active service and blocked bay time. Check those totals against the complete arrival-to-receiver durations. Finally introduce an unlimited holding comparison and determine the minimum holding capacity required by its actual interval overlaps.
The problem changes arrival gaps, processing duration and receiver intervals. Begin from the event dependencies instead of copying the earlier table with new headings. State why a finished unit remains on the bay in the first model and why it can leave in the second. An independent explanation should identify the changed state capacity, not merely say that the second system is faster.
CHAPTER 25 OF 29 · Check evidence and transfer
25. Check the changed timeline and its limitations
Without holding, starts are 0, 4 and 7; service completions are 2, 6 and 9; bay releases are 4, 7 and 10. Queue waits total 0 + 3 + 5 = eight minutes. Active service totals six, and blocked time totals 2 + 1 + 1 = four. The sum is eighteen unit-minutes.
Arrival-to-receiver durations are 4, 6 and 8, again totalling eighteen. In the unlimited-holding comparison, service starts are 0, 2 and 4 and completions are 2, 4 and 6. Holding intervals are [2,4), [4,7) and [6,10), so two positions are needed during [6,7).
Receiver acceptance still occurs at 4, 7 and 10. The same distinction survives the changed numbers: the bay can release earlier without the final receiver sequence changing. The interval-overlap check also shows why one holding position cannot simply be assumed sufficient because the first two holding intervals meet neatly at an endpoint.
In the changed three-unit example, exactly one holding position produces a useful intermediate check. A leaves the bay at 2 and holding at 4. B completes at 4 and can enter holding immediately after A leaves, remaining there until 7. C finishes at 6 but must retain the bay until 7, then occupies holding until 10.
The bay-release times are therefore 2, 4 and 7. Pre-service waits total three minutes, active service six, blocked bay time one and holding time eight. Their sum is again eighteen unit-minutes. The one-place system removes some blocking without becoming equivalent to the unlimited comparison. This gives an independent changed-context check of both the event-order convention and the finite capacity constraint.
CHAPTER 26 OF 29 · Check evidence and transfer
26. Build a record that distinguishes the physical states
For a real evidence review, identify the unit and visit, the bay, the observed start and completion events, the resource-release event and the relevant downstream condition. Keep a planned release separate from a confirmed one. The definitions should be agreed by the people who own the corresponding work and records.
If a completed unit remains present, record what is known without assigning an unsupported cause. Was the next place unavailable, was a separate decision outstanding or is the event record incomplete? The numerical duration identifies an interval to investigate, not the cause or the appropriate remedy by itself.
A good record also preserves the population and horizon of any summary. Excluding incomplete visits, changing the meaning of release or counting an internal relocation as a final departure can change a report without changing the service. Trace one unit through every state and reconcile the relevant counts before treating a smooth dashboard as evidence that the underlying handover is complete.
CHAPTER 27 OF 29 · Check evidence and transfer
27. Repair, stabilise and extend the learner's route
For repair, use four cards and one marked bay. Turn a card over when its service finishes but leave it on the bay until the next receiver opportunity. The physical card makes the distinction between completed work and released space visible without visiting or imitating an operating yard.
For stabilisation, reconstruct the first two rows from arrival and release events, then complete the table independently. Add the time categories across units and check the arrival-to-receiver total. If the accounts disagree, find the missing state instead of changing a departure time merely to make the sum balance.
For extension, add one holding place and track its occupancy intervals. Then change a processing time or receiver schedule separately. The education parent supports this progression from a concrete model to symbols and independent transfer. The learner’s achievement is an explanation that survives a changed constraint, rather than a memorised queue formula detached from its events.
CHAPTER 28 OF 29 · Check evidence and transfer
28. Questions that keep resource release precise
Does completed service mean that the bay is free?
Only if the relevant release event has occurred under the model or actual approved arrangement. Finishing one task does not by itself remove a physical occupant.
Does more holding space always improve final departure time?
No. In the original comparison it frees the bay sooner while the receiver sequence stays unchanged. Other systems and objectives need their own analysis.
Are active utilisation and physical occupancy interchangeable?
No. The original bay is active for 60% of the horizon and occupied for 100%. The blocked state explains the difference.
Can a card model authorise a site change?
No. It explains dependencies. Actual space, movement, equipment and release decisions require the site’s competent and authorised arrangements.
CHAPTER 29 OF 29 · Check evidence and transfer
29. Continue through the handover that remains unresolved
Rebuild the complete yard account
Return to Yard Management for identities, physical records, equipment and responsible handovers. Its broad account makes clear why a processing timestamp, a confirmed location and an authorised release are different evidence.
Choose the related timing question
Use Arrival Clustering and Queue Recovery for arrival patterns. Use Finding Unbroken Bay Time for continuous calendar feasibility. Keep the occupancy interval appropriate to the defined release condition when moving between these lessons.
Carry the state distinction into another subject
The Gold Standard education parent connects explanation with independent checking. The How X Works hub offers adjacent subjects. Carry forward the question: has this resource actually been released, or has only one activity performed on it finished?