Neither. When I have place, I refer to wait list and see how wanted space closest to timing the place opens. I contact that family, see if still looking care and if so, set up interview. If several family wanting similar start, I contact all and set up interview. Then I pick who I would prefer have. If none are what I want, I advertise space or contact other on wait list who need care soon after place is vacant.

I rarely contact people on list if their start date has passed unless it really recent because not all parent like the care they sign up for and tend switch in first 2 month if that case.