Progression from 3x10 FTP to 3x15 FTP

Maybe break up the 45min (3x15) in any way manageable, even if more than 3 reps; then build from there! Just another way to crack it.

TBH pretty in the weeds here, and if you’re almost finishing the 3rd, I’d do the 2x15 then just keep creeping up the duration on the 3rd. You’ll be really motivated to get there and that will be a nice boost!