I have been asked to make 3 "designer" bag cakes all due for Saturday. They are VERY time consuming for me. I was hoping to tackle them one at a time and be ready Friday night but I'm afraid that fondant will be rock hard at delivery time. Any suggestions for keeping that fondant from becoming a brick??? (The fillings are all butter cream on all 3 cakes so I'm not worried about them sitting in a fridge). Any ideas? Thanks a bunch!!