How big is your BP and what is his setup like (enclosure size, temps, type of thermometer used, type of hides (how they tight like a shell on a turtle's back), substrate used etc).
How do you thaw and warm the prey up? Where do you feed? How do you offer (dangling or held from behind the neck moving it as it was alive)
How many f/t has he had with the breeder?
Generally speakin I would not consider an animal switched to f/t unless he has had at least 5 successful consecutive F/T.