I am delivering a 4 tier wedding cake the day before the wedding because of vacation.It is fondant and starting to get hot in Ga..Do i need to have her store it in REf?First wedding fondant cake.HELP!!!

If you are delivering the day before the wedding I would have her store it in the fridge overnight depending on what time the wedding is the next day.
Is the wedding inside or out?
I have a 3-tier I am delivering Friday for a 50th B-day Saturday because I too am going on vacation Sat. I am haveing them keep it in the fridge until Sat. Morn because their party doesn't start until 6pm. that way it will have plenty of time to get to room temp. before the party since it is very warm here as well.

Unless you've stored your fondant in a fridge before and know what will happen, i wouldn't chance it. Of course, it'll depend on your fillings and whether or not they will be okay. I don't make fillings that have to be kept cold, due to my fondant cakes cannot go in the fridge. I live in florida and when I take a fondant cake out of fridge, it sweats like crazy. Always dries in a couple of hours, but I wouldn't chance colors running or any other problems on a wedding cake.

A cake covered in fondant is completely sealed and should be fine delivered the day before.

I think it would be ok, unless the filling needs to be refrigerated.