Thanks for the feedback. I'm not convinced its a bug, and since that one crazy day with 5 'not on schedule', theres only been MAYBE 1 or 2 a day (and none yesterday).
At this point i have a feeling its user error.
JBS: About 30-40 patients per day.
Ill check out the audit log
We have 3 staff who would add appointments. No noticeable majority of 'drops' from a single individual.
