40k TT plan is great for building sustained power, which is what a 10m TT is. I’d question racing midweek every week though, and racing at weekends, as you could find that you end up losing fitness as your aerobic base could diminish.
I recently asked the same question on another forum and TR gave this reply:
Sprint Distance Triathlon races usually have a 20km TT bike leg, so that’s the specialty plan we’d recommend. Don’t think of the 40k TT plan so much in distance as time; that plan prepares you for ~1hr long effort (near-FTP). Whether that’s applicable to different distances depends on the course and your capability.