01Check the actual constraints
A free calendar slot does not establish that a job can happen. Map the staff, agreed qualifications, equipment, materials, site access and travel assumptions relevant to your operation. Distinguish a tentative reservation from confirmed allocation and identify the source that owns each availability decision.
02Update all affected work
When a job overruns or materials are delayed, identify the other allocations affected. Route the change to the planner with the reason and current customer commitment. Staff should be able to see which schedule is authoritative rather than choosing between an inbox, spreadsheet and calendar.
03Record the override
Some conflicts require an informed human decision. Record who approved an override, the constraint being overridden and the follow-up required. Keep unresolved conflicts visible and avoid silently allocating the same person or item twice when two users save changes close together.