Everything was sounding good this lesson! You should be happy with all your improvement :)
Work on those descending major scales. Its a nice mental work out to do them back wards, and going in to your low register will get the blood/ air flowing in your favour. In the pedal register (below F#) try to open that jaw up and relax the aperture while keeping the corners engaged. Use your ear to guide you to the end of the scale.
Your slurred harmonics are coming together as well. Remember when you struggled to get 3 notes? Now you can slur two octaves! :D Try the exercise we did where the top note stays the same then you eventually shift them all up. Ex. Cmaj 4 notes, Amaj 5 note, F#maj 6 notes, the top note is always E. From there you can shuffle everything up which will give you a serious work out. If you get light headed take a break and doing some full breaths.
Etude in D is getting better. Im glad we discovered playing 8th notes constantly helps you with the rhythmic accuracy. It sounded much better after that. Always be aware of the air moving forward to create a beautiful sound! You’re good for that most of the time but when your get tired it sometimes goes out the drain… those are the times to engage your core and give it a little more air support! Keep working on those first 8 bars and try to get comfortable with the next 4 or 8 for next lesson.