In most restaurants Croquembouche or chocolate profiteroles are served only the day they are filled.
Croquembouche or profiteroles are the same as eclairs, just round instead of long.
We usually made only a small amount and most of the time they were all sold by the end of the day. Any leftovers were eaten by the wait staff and never made it back into the kitchen.
In a pastry shop I would have a few filled for display only and fill them to fresh as I sell them..