Appreciate the thought, but I currently have a balance of 455 points in my account. I'll pay the $31 & earn some points. Remember, I only do HOM-CHI 1x/year for CSE, and haven't in a few years due to covid & then conflict on dates. Last year I redeemed points for business RT HOM-CHI (and last year biz still got you into the ML for free). Any points I earn on this trip I'll save for future Chicago trip or, if I get the train bug, start saving towards future long haul.
Cheers.