I moved from Waltham to Everett, two towns in Massachusetts just outside of Boston, on January 1st. When I did so, I changed my address with all the necessary bureaucracies and, because Massachusetts law requires it, sent in a new voter registration form with my new address. In retrospect, that may have been a mistake.
At issue are two Massachusetts laws. The first is that you must register at least 20 days before the election. If you do the math, you can see that it was physically impossible for me to register with my new address once I'd actually moved here and still vote on the much talked about special election on January 19th. It didn't occur to me to register here before I moved--I'm not sure that's even possible. But, if you move away from an area, the second law allows you to still vote there for up to 6 months after. However, if my new registration has caused my old precinct to purge me from the rolls, then I may not be able to vote there either. I was not aware of this law until I inquired, else I would not have sent in a new registration until after the special election.
So what am I going to do? Since I couldn't find specific contact information for the city of Waltham's election commision, the only option I can think of is to show up at the polling station on January 19th and see if I'm on the roll. We'll see.