DH and I are heading to WDW Dec 9-16. We plan on Dec 10 to do EPCOT and the CP in order to see SCC. Originally, I had that day scheduled for us at Universal with EPCOT later in the week. I also have a ressie for CM the morning we were going to do EPCOT and I want to change the ressie at CM to coincide with the change in schedule. Should I book the CP and call back later in the week to change the CM ressie as not to tie up phone lines to people trying to book packages, or should I do change the ressie Monday while I have Disney Dining on the phone?