If it's after the count day, you're okay to stay.

DCPS parent here: I don't think this is a problem and know families who have done that. I personally wouldn't think of that as a residency fraud since these seats won't be filled with students until next year anyway. Given how touchy this subject is, I wouldn't make a big deal of it. But I'd inform the principal in person and seek guidance on how to do this so it doesn't make it a problem where there is none. And remember that the worst case would probably be that you may receive a small tuition bill for that month or two, well worth paying to not put your child(re) through a transfer at the end for the school year. That's in the interest of everyone.

How does your school handle it if someone moves out of DC a month or two before the end of the school year, but would like to continue sending the child to the same DCPS or charter through the end of the school year? We might be in this situation next year. I don't want to be a residency scofflaw, but am wondering what schools' practices are in this situation.