Well, here's the thing:
1. Rickenbacker, unlike other manufacturers, dates the warranty from the date of
manufacture, not the date of sale. So, if this bass sat in MF's warehouse for 15 months, your warranty has expired, and exchanging it for another one from MF is your only
real recourse. Unless, of course, you want to keep this one.
2. Run your serial number to see when it was made. RickResource.com is a good place to do that. That will tell you if there is any warranty left. It will also tell you if it is one of the notorious 2011 JetGlos, which had problems with the finish cracking off around the tailpiece.
Lots of (understandably) angry posts on the Rick Club forum about that, and IIRC, most all of them came from MF buyers. They must have had a ton of them in the warehouse, and whether or not it was the result of a bad paint job, poor quality control, or gremlins, sitting around in a cold/hot/cold/hot warehouse for a couple of years doesn't do anything good for a finish.
In any case, it's up to you whether you decide to keep it or not. Hopefully, it's just a smudge or something that will polish out. If it
is one of the Ricks that they had problems with, and it is a crack in the finish, be aware that it could get a lot worse in the future. Good luck, whatever you decide!