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Change and cancel restrictions based on reserve in advance settings
The restrictions that apply to submitting a reservation regarding the reserve in advanced setting (e.g always reserve for making reservations in advance (like needing to book at least 3 days in advanceahead) are also taken into consideration when trying apply when a user wants to change or cancel a reservation. If a user would not it wouldn't be allowed to submit a reservation based on make the reservation at the current time vs start time of because it's too close to the start time, then the user also can't change or cancel it.
This is because trying to change it could lead to problems when re-submitting the reservation, it is also not allowed to put that reservation to change or cancel it anymoreand it's hard to predict which changes would be allowed. Since if changes aren't allowed, cancellations aren't allowed either. These change and cancel restrictions are under the assumption that advance booking restrictions are setup to prevent last-minute reservations or changes for certain resources.
Conflict and restriction exceptions
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