How to save your top layer:
1. The night of the wedding, have someone take home the cake and put it in the freezer for you while you're on your honeymoon. This is just to solidify the icing so it doesn't become totally crushed.
2. Wrap it first in plastic wrap.
3. Wrap it in aluminum foil.
4. Wrap it again in plastic wrap or put it in an air tight plastic bag (getting as much air out of it as possible)
5. Store it for a year.
6. Order another replica so that when you don't feel like having more than a bite, you've got a backup!