You can try any time. If it won't take frozen/thawed then give live. Always try the F/T first. I've found that once my new balls are well settled in and comfortable in their new surroundings then feeding is rarely an issue. A regular schedule is also helpful. I like to feed Wednesday mornings before going to work, (pull the frozen on tuesday night and let it thaw out overnight) My snakes know the schedule better then I do and are usually sitting up at the front of their tubs when I turn the lights on Wednesday morning.