Last night I finished up some cupcakes my putting on the fondant decorations. Then I  was all paranoid that my cardboard bakery boxes would dry out my cupcakes so I put them in an airtight container.

This morning when I uncovered them the fondant had a slight sheen and some of the curled ribbons were droopy. :(

Was this from sealing them or from putting them on the BC too soon?

This is from last night, now the ribbons are laying down and stars are softer. They still look good but I want to prevent this in the future.

AI had some problems like you last month and thinks was for temperature because was very bad weather time don't know if you have the same problem

My guess is both.  The fondant probably absorbed some moisture from the buttercream AND being sealed kept the moisture in.  You can keep dry fondant toppers alone in a sealed container, but the moisture from the buttercream and cupcakes had no where to go but in to the toppers.  Very pretty cupcakes though!

Those plastic "clamshell" cupcake containers are super air tight...and will keep cupcakes super fresh...but I had them soften my fondant topper before.   If I recall, the topper hadn't sat and got super hard so I'm not sure if that was the reason.   Now, I put my fondant topper on at the last minute. 

AI had that problem with some fondant Dinosaurs and their legs broke off! Now I make all my cupcake decorations out of gumpaste .. It doesn't soften once it dries... Most people don't eat that part anyway.

That's because you covered them. My suggestion is to keep them in the box but leave the box a little open.

Thank you everyone!

The science geek in me wants to chip in ;) the reason cupcakes and cake goes dry is because the water in them starts to evaporate. If you keep it in an airtight container, the water will soak into the cake again. If you have fondant in there, some of the water will soak into the fondant instead, making it softer.

Sorry you needed to hear that, just wanted to get it off my chest ;)