As you know, every BP is different so there is no hard and fast rule. I had a girl last year that would not eat and I tried everything. I finally decided to assist feed her, 4weeks after her first shed. And I had to continue to assist feed her for the next two months and then finally one day she just decided to do it on her own and now she is one that never misses a meal. And I had no trouble switching her over to rats either.