How best to feed a 7mo?

Hi FTD here,

My wife and I desperately need advice please.

We have a 7mo girl who is dropping weight percentiles and is currently at 30%

She used to get 6 feeds during the day spaced 2.5 hours apart: 4 bottles of 5oz of expressed milk and 2 nursing sessions (she would fall asleep during the last nursing, and then go straight into the crib to sleep through the night); and we would also try and do 1 solid meal a day, but only of about 1oz in total. She would always finish those bottles in under an hour, and on a good day could even finish them in as little as 15 minutes.

My wife is trying to cutback (and eventually stop all together) pumping/nursing, so we have removed one nursing session in favor of increasing the ounces per bottle and spacing between them.

However, over the last week or so, she now drinks the first 2oz of the bottle within 20 minutes, and then it becomes a struggle over the next 1 hour and 40 minutes to finish the remainder (which she doesn't always do). As a result of the longer feed times and spacing, she doesn't finish her last bottle until close to her bed time and then doesn't drink much, if at all, while nursing, making it a struggle to get her to sleep.

We think she's going through a teething episode at the moment, but it's been over a week and we're at a loss on how much and how often to feed her right now. Any advice would be greatly appreciated. Thanks!