Hi Jakob, to be honest all those questions need to be answered by you. Listen to your body and chops and put the horn down when they are tired or start to swell. When I first started MTM I only managed 10-15 min studying the concepts. This created a new ’embouchure’ set for me and as I had regular gigs I had to swap between my 2 embouchures for the 1st 6 – 12 months. I always started with the MTM routine, then tried to stop analysing and just and play after that (That’s the hard bit). Sometimes starting gigs with my new setup then reverting to the old to finish.
I concur with what Eric, do MTM exercises at the level you are at for as long as your MTM chops are fresh (10 – 40 min depending), then have a break, then try just playing etudes, standards or improv in your next session and think more about the music not the technique. Eventually your mind and body will start preferring to play with your MTM setup. After 6-7 years of MTM I use various advanced exercises in my technical routine that I remember from the system and also apply the concepts to other exercises like Schlossberg, Arban, Scales and Arpeggios etc. My routines also depend on my commitments at the time from 20 min a day, to multiple 40min sessions a day. Hope I have helped. Good luck!