I’ve got a remote on my minoura, just left it in 3 out of H-5-4-3-2-1-L the whole time and use gears, means warmup is in the 34t ring and the actual session is in the 50 which works well.
Don’t confuse variable resistance with max resistance, my minoura is harder in 4 than the cyclops that preceded it was flat out.
Also use some sort of power measurement, trainerrroad and dongles/sensors are cheapest although prices of actual power meters are dropping all the time. It’s deceptive how easy FTP feels for the first few minutes, even 20 minutes at FTP isn’t particularly hard, just wait for the end of the second 20min, or the third.