B2 在…方便的时候
when you want
The goods will be delivered at your convenience. 货物随要随到。
The machine records your messages and you can answer them at your convenience.
There's no urgency, so please don't make the journey other than at your convenience.
The documents are ready for you to pick up at your convenience.
I would appreciate the chance to meet with you at your convenience to discuss these matters.
See also: convenience (BEING EASY)