Try this
- State the unavailable time and any travel or rest buffer you want to reserve.
- Choose a new shared window if the old one conflicts. Use a neutral calendar label if the reason is private.
A worked example
“I’m unavailable Wednesday afternoons for the next month. Could we move our shopping plan to Thursday?”
An invented example to adapt, not a real exchange or a script you have to follow.
Before you leave it here
The information needed for coordination may be only the time boundary. Do not make disclosure of the appointment’s details a condition for changing the plan.