I left a few months ago, and when I logged on recently to check out the new stuff and went into the Armory my rank went up a whole bunch from what I left it at. That's not a big deal, but I didn't get any of the CC rewards for ranking up, which does bother me a bit. I am close to 50 now, so I can FINALLY start earning CC from the matches I play, so it's not a problem, but I was just looking for an explanation as to what happened.
Also, it seems like all my weapons went back to stock, and I even lost progress on some of the newer ones. I haven't done anything with BFV for 3 months, except update it. I didn't uninstall or anything.
XB1, by the way.