Every operation has a version of this conversation. Usually it is held from memory.
Why it matters
Schedules are edited by several people under time pressure. When something goes wrong a week later, the question is not who to blame but what sequence of reasonable steps produced an unreasonable result. Without a record, the answer is a reconstruction, and reconstructions tend to confirm whatever the most confident person remembers.
A replay also makes improvement measurable. If you cannot see what changed, you cannot attribute what improved.
How you notice it slipping
Disputes about the schedule end in opinion. Nobody can tell whether a change was made by a person or by an automatic process. The same mistake recurs because its cause was never actually established.
What to do
There is a second use that matters more over time. A replay is the only honest way to answer whether a change helped, because it shows what the schedule looked like before anyone touched it.
Keep the history at the level of the appointment, not the batch, and keep the reason alongside the change. Then use it in the weekly review rather than only in a crisis — read as a pattern, a change log is one of the cheapest sources of improvement an operation has.