My output pattern is all over the place too, 13 months post surgery.
I too was advised to change the appliance first thing in the morning, when output would be less. I have found that I have a smoother process of changing if I have an early dinner (5:30-ish), and then change my appliance at 9:30/10:00 pm. Only once or twice in the evening have I had that everlasting cycle of output during a change, for the most part it seems to be a quieter time for my body. My system also seems to be quieter mid-morning. If you have flexibility in your schedule, you might want to play around with changing at different times and see if there is a better option for you.
Hang in there. Wouldn't it be nice if our stomas came with a one-size-fits-all manual? :)
Dx Mild Proctitis 7/06 at age 33, Dx Severe Pan Colitis 5/07, Dx Crohn's Colitis 10/07
Failed Asacol, Lialda, 6-MP, Canasa, Rowasa, Proctofoam, Entocort, Remicade, Humira
10/10/08 colon removed, temporary ileostomy
11/10/08 FINALLY off prednisone after 18 months
2nd of 3 surgeries planned for '09 to form j-pouch