I'm going to be doing a cake that will be frozen for about a week. I've frozen fonfant cakes with no problems. But this one will have lots of red,and the thought of the colors bleeding is giving me anxiety. :) So, I can go two routes; a red solid base color with white polka dots or white base with red dots. Which would work best? Or, does it make sense to do a white buttercream with red fondant dots, or would the dots bleed down the white buttercream? By the way, I have zero time to do a trial run. 

Thank you!!!!!

Why can't you freeze the cake with just the white buttercream, punch out the red fondant dots and freeze them separately and then just apply the fondant dots after the cake comes to room temp.  Everything is ready, but you'll just stick the dots on the cake at the last minute to avoid bleeding.  

I realize this is an older post but I just wanted to comment with an update, incase any one else has the same question. :)  

I ended up doing a red base color and put on white polka dots.  I couldn't keep them separate, as I was having to have the customer (who is a friend) freeze the cake herself (she needed a cake while I was going to be out of state).  I did have her apply the stand up pieces that were made from Gumpaste, which I just let dry out myself, then kept in a sealed container for her to keep until they were ready to pop into the cake.

However, the white polka dots, I applied when I decorated the cake.  I prepped the cake for freezing, delivered it, she froze it, thawed it a week later as I instructed her to do so and there was no bleeding of the red at all!  My worries and anxiety were for nothing! :)  Whew!