Hope all goes well with surgery and recovery for baby mia!
I know they say to go to a sippy cup after surgery but my Kylie wasn't having it. I just used the haberman feeder for the first week because her mouth was so sore and her haberman was the only thing she would take. The doctor said it was fine. My daughter doesn't quite have the coordination to take a sippy so she is using the Vent Air bottle & we widen the nipple. It seems to work out great. When she's a year old we'll start using the sippy cups. (She's 11 mths right now, like Mia)
Kylie had her soft palate repaired when she was 9-1/2 mths old.
As far as pain relief, we used Tylenol infant drops and also Tylenol suppositories. I know...no fun for baby, but it relieved the pain quicker and was recommended by the oral surgeon.
The first 24 hours are most definitely the hardest but if she's like Kylie, you'll see a big difference after the second day.
I will your family all the best!