I don’t recommend covering a frozen cake or even one that has been refrigerated longer than 15 minutes as you risk a blow out in your fondant. As cake returns to room temperature it will release gases and any trapped air will be trying to escape which can result in a huge air bubble developing under your fondant. This is more likely to occur in summer. But trust me it is heart breaking to see your perfectly covered cake develop one of these bubbles many hours later.
