Understanding booking conflicts and vehicle availability
MobilityManager guarantees that a vehicle can only be reserved by one driver at a time. This article explains how availability is calculated, why some bookings block a slot and others do not, and how the system prevents double-booking.
What "available" means
When you search for a vehicle for a given window, the system returns a vehicle only if no other booking occupies that vehicle for any part of your requested period. Availability is computed on the exact start and end instants you choose, using the same values that will be stored if you book — so what you see as free is genuinely reservable.
Which bookings block a slot
Not every booking counts against availability. Only bookings in an occupying status hold a vehicle's time slot:
| Status | Blocks the slot? |
|---|---|
| Pending / PendingApproval | Yes — a booking awaiting approval still reserves the window. |
| Confirmed | Yes |
| Active | Yes |
| Completed | Yes (historical use of that window) |
| Cancelled | No — the window is released. |
| Rejected | No — never occupied the vehicle. |
Note: Cancelled and Rejected bookings deliberately do not block availability. As soon as a booking is cancelled or rejected, the vehicle is immediately bookable again for that period.
How overlap is detected
Two bookings overlap when one starts before the other ends and ends after the other starts. The rule is a half-open interval: a booking occupies its window from the start time up to, but not including, the end time.
The practical effect is that back-to-back bookings are allowed. If one booking ends at 12:00 and another starts at 12:00 on the same vehicle, they are not considered to overlap. Any actual time overlap, however, is treated as a conflict.
What happens when there is a conflict
If you try to book a vehicle whose window overlaps an existing occupying booking, the booking is refused and you see "Vehicle not available for selected time". Pick a different vehicle, or adjust your times so they no longer overlap.
Preventing double-booking under load
Availability is re-checked at the moment you commit the booking, not just when you searched. This closes the small gap where two people could both see the same vehicle as free and try to book it at once:
- The booking is written inside a strict, serialized transaction that re-verifies there is still no overlap immediately before saving.
- If another booking has claimed the window in the meantime, your booking is rolled back and returned as a conflict — for example "Vehicle was just booked by another user. Please try again."
In that case, simply search again and choose another vehicle or time.
Tip: If you frequently hit conflicts on a popular vehicle, widen your search to other vehicles in your accessible pools, or try adjacent time windows — back-to-back slots are valid and often free.
Availability and your access
Availability is always evaluated within the vehicles you are allowed to book. A vehicle that is inactive, has no pool, or sits in a pool you cannot access will never appear as available to you, regardless of whether its time slot is free.
Related
- Choosing start and end times, and how times are handled
- Book a vehicle yourself (self-service)
- The booking calendar view
- Which vehicles and pools you can book
