I think Sandisw cleared it up for you but it's the calendar date logic that you have to drop -- it took me a bit to move past that as well.
Think of it as whatever UY the points that are being transferred are at the time of transfer, regardless of what UY the sending or receiving memberships are currently in, that's where it counts, and it doesn't matter what month the contract UYs are.
I am currently in my 2025 UY (December contract), but just transferred in 2027 UY points (from someone who is currently in their 2026 UY). That means that even 2.5 years from now in Fall 2028 when I'm in my 2027 UY, I will still not be able to transfer in any additional 2027 points or transfer out any of my 2027 allotment. Similarly, the person who transferred me points would not be able to transfer in or out any 2027 UY points, even next year.