I did this last year. The fine print states that if you buy the maximum allowed per day (two full price and two half price), all credits must be used that day. Nothing about expiration dates is mentioned if you only buy one get one half off per day. They never expire. I watched a cashier change the expiration date from the standard two weeks to a date that was years in the future, presumably because they have to put a date. I bought a total of eight plans, but never more than two a day. I was still using them over half a year later with no problem. Also, you do not have to use any credits at the time of purchase. If you frequently visit and prefer buying rather than packing food, I would buy two plans with each pass every day you are there during the promotion and then you will have food for many months to come.