Rice cereal for reflux?

I had an epiphany about my baby’s sleep- she’s been up every 1-2 hours for the last month, and I just realized that that was about the same time I had to take the wedge out from under the head of her crib because she was wiggling around so much and ending up upside down and sideways. I am wondering if laying flat all night is making her reflux worse (started Zantac at 2 months and raised the head of her bed and it worked wonders)

She falls asleep for most naps and all bedtimes independently, I know she can put herself to sleep, and there’s no way she’s hungry every 1-2 hours all night... so I’m thinking maybe it’s the reflux?

I plan to ask the pedi about starting to give her a spoon of rice cereal with every bottle to help her food stay down, I know a lot of people recommend not starting solids until 6 months- I’m just wondering if anyone has had a similar experience or any insight?? Thanks! :)

She’s gaining weight okay, but she’s very tall and skinny- 48% for weight and 99% for height... she spits up at least 4-5 times an hour all day... I’m hoping a little cereal with every feeding might help keep things down and help her at night? We’re on Zantac but I would be willing to try Prilosec.