[amsat-bb] AO-51 mode changes

When AO-51 changes modes, what time is the change generally done? For example, the schedule says that AO-51 will start broadcasting 9600 baud telemetry on 3/10 (today).

Is this done in the morning on the east coast, is it preprogrammed to happen at some specific UTC time, or what? When are these changes actually made? It would be nice if the schedule announcement had some additional precision, something like: on orbit-xyz during the pass over the abc groundstation, the mode switch is planned.

thanks, jeff AD6EO