Hi! 

I’ve just done my first wedding cake for a friend of a friend, and while it looked fine in the end, by the time they served it, it was dry!

Ive used this recipe many times before and had the same batch of friends try it just the past week and it was amazingly moist...im not quite sure where it went wrong?

i had all the layers plastic wrapped before frosting, and because i used cream cheese frosting I had it refrigerated overnight (decorated the day before delivery). Do I need to be wrapping the chilled frosting if its going to be in the fridge? Or do i need to find large enough containers to store each tier in if they need to be refrigerated? 

Or am I missing something completely? 

How are you storing your crumb coated and/or decorated tiers?  I always put my crumb coated/decorated tiers in cake boxes and then into the fridge.  The only exception is if I'm crumb coating and frosting a cake at the same time.  Then I just leave the crumb coated cake in the fridge/freezer for 20 or so minutes and then frost.  But after that it goes into a sealed box and then into the fridge.

was the cake made with butter in the batter?

if it did have butter in there -- that might be the culprit -- because the butter does not relax back to out of the oven softness even at room temp -- test it next time you bake -- put a piece in the fridge -- let it naturally come to room temp -- no icing --  take a bite and compare it to a bite of the one that never saw the fridge -- it's a tighter texture -- it scrapes a bit down the back of the throat -- people say "it's dry" but it's not dry because you can restore it with a few seconds in the microwave -- it's that the butter firmed up --

Your response makes perfect sense, -K8memphis.  The way you stored the layers and the cake are not cause for drying out, as best I can see.  I've kept my completely frosted cream cheese cakes in the refrigerator over night without them being in a box or wrapped and they were fine.