I am having trouble with my Buttercream shrinking.  I get it beautifully smooth and if I let it sit out overnight completely decorated there are places that almost look like the have shrunk and take on a wrinkled effect. If I keep the cake in the fridge overnight it looks great. Not all cakes can go in the fridge overnight if they have royal or fondant elements. This is limiting my time frame to work on cakes. Any body else run into this issue?  Its not the buttercream, I use high ratio and Edna DeLacruze recipe.  Please help...would love suggestions.

AIt sounds like it is getting hot and sliding off the cake. I have never heard of buttercream "shrinking." If it looks wrinkled and isn't where it was, it sounds like it is melting and sliding. Especially if it is fine when refrigerated.

N, maybe shrinking is not the riggt word...its hard to describe. Its not sliding off, it is usually where it gets an air bubble/ pocket that you don't see when you first smooth it. Then, around the air bubble it shrivvles up. I can use a fondant smoother and get it out if there are no decorations there. Its just so odd...I've never had this happen until lately.