I just had revision surgery on 1/30, band to sleeve! I had it all in one surgery as well as a hiatal hernia repair! I was under for about 3 hours! All went well! When I asked my Dr why Drs sometimes do it in separate surgeries he had 2 answers, first of all it depends on the pt and comorbities, how long can someone tolerate anesthesia ? Since just having sleeve surgery you are under for about 1 1/2 hrs! The second answer was interesting he said if he did in 2 surgeries he would make more $$$ which is so true ! Also in addition the pt has to take 2 separate LOAs if working! So in the end I would look for a surgeon who did it all in one surgery! good luck