I assume you are speaking of Saracino fondant??? With a fondant or modelling chocolate covered cake, since the cake is sealed by the fondant, it can stay fresh 3-4 days. I wouldn’t chance any longer. And any fondant can be affected by direct light. If exposed long enough, colours can fade. That’s why it’s best to store a cake away from direct sunlight, in the coolest area possible.
Creativity is God's gift to us. Using our creativity is our gift back to God. Clarky's Cakes 😎