That's really helpful, I didn't know I could look it up that way through chase online. I just checked mine, and even though I just got the "card renews soon" email, my chase summary states clearly that the benefits reset after my 02/2021 statement. I guess it's a little delayed relative to my card application date. So it looks like I'll have no problem using the benefits with my upcoming trip in January, and then closing the card in Feb afterwards.

I'm still curious to learn the actual policy answer to my question though, just for future knowledge or for the sake of others in a similar situation.

As a related side question, I wonder if it would work to make a dummy booking with my $75 card travel credit asap (like find a ticket costing nearest up to the credit amount), then cancel it after a couple days to turn it into saved flight credit, then convert the saved flight credit into points, which I believe I could do until Dec 15, right? That way I could avoid the card travel credit simply expiring and have equivalent points for whenever. Yeah, it's a lot of fiddling around for not a whole lot, but eh, I don't have much else better to do.
[edit: I dug around another FT post, and found the easiest solution is actually to buy a SW gift card with the travel credit... I'll leave this up here in case it helps anyone else.]