i have a an administrative assistant who keeps track of a doctor's surgeries
in a recurring appointment (the doc aloways operates in a specific blcok of
time on tuesday, when the OR is available to him).

as the surgeries are shceduled, she adds the names to that day's surgery
(the instance).

she changed the subject and it wiped out the names of all the surgeries in
the past and those scheduled for the future. is it possible to undo this?