Honestly, if I were writing the code for this, it would probably work the same way.

This is a one-off thing, so it's not worth the time to build it in a way that will work for a decade.

And how do you want it to work? Do you want the rollover to post on Jan 1, where it might be missing something, and then have them issue an adjustment later? Or do you want them to wait until Jan 31 where 99.999% of flights from 2025 have posted, but you miss out on milestones for a month?

I prefer the former.

Heck, if I were building this, I might not even have automated it. I might have just run a SQL query once a week in January, and then let the missing-SQC people deal with any one-offs after that.