I was wondering how long in advance I can make MMF before I need to use it? We are traveling to the beach for my sister's wedding and I will assemble the cake there. I want to have everything pre-made, cakes, BC, and fondant. But I woulf have to make it this weekend the 7th for a wedding on the 17th. I would use the fondant on the 15th. I'm thinking it might be hard as a brick by then? So, how long can fondant sit on the counter and still be usable?

Wrap it well - I do plastic wrap and put that in a Ziploc bag - and it'll be just fine. You may need to knead it a little, but it won't go rock hard if it's wrapped up.

Woohoo! Thank you! This will save me a ton of time once I get there!