A minor point --- United does already know about all of the flights you have booked with them. You can see them when clicking on the Future Flights tab on mystatus.united.com (mostly ... that total doesn't include some purchases, at least for me). However, since flights can be cancelled or otherwise not flown by the passenger, we all know that credit isn't awarded until the flights are completed.

Which does nothing to resolve the question of why the OP thinks United knows he'll be 1K again but has not yet awarded the points, or (another possibility) why he thinks his points expiring at the end of January would be extended.