I would freeze them immediately. They defrost beautifully and are DELICIOUS. We buy the Cinnamon with nuts several times during the year for parties, and there is rarely a crumb left. I have a friend who even cuts herself a piece to take home!!!
They freeze beautifully right in the box and defrost on the counter (or if you're cutting yourself a slice you can speed that up in the microwave!).
We've been serving these cakes for YEARS.
ENJOY ... what a fabulous gift.
Edited to add... if you are giving as a gift, take it out the day before and leave it on the counter.