YP do not make as good a forage as BG, since they 1) spawn but once a year and 2) compete with LMB to eat small fish. IIRC YP tend to need restocked periodically in the presence of LMB.
That said, I think I'd take the cheap DNR YP and stock BG on my own (if possible - ain't NY a more permit controlled state than most wrt pond stocking?).
Follow-up stocking time for LMB would depend on their size AND YP/BG spawning. You want those bass to fall asleep hungry and wake up with their bellies full (to quote the Muleshoe Motormouth) of forage about 1/3 their body length, without having to eat your original forage fish stockers.