I should first mention that I have the same issue on Xbox 360 and Yes, I did buy ops. It seems like this may be happening somewhat randomly with the only common thread being a person bought ops after an update, so if I may make a suggestion....it may be a particular op that is bad and as players trigger it, it is finding an error that is causing ops to crash. Just my two cents from seeing things like this in the past as a Senior Game Producer myself.
I have the same problem with the operations, when clicking "operations" i get thrown back to the start screen of ghosts where "online play" and "options" are shown.
This happened after i updated the operations with 1 squad point a couple of times in a row.
I've had this for the last 2 days and no change.