Supply dip question

hlc820

Super quick background. I had OS and OALD. All is better with block feeding. LO is an mspi baby and I have been on the diet for almost two months with success. He is also a reflux  baby on Prevacid. I feel like my supply is dipping out of nowhere. I struggle to get 5 ounces at a pump session. 5 ounces used to be pretty standard. I also don't get as full overnight. I pumped before bed last night at 8:30 and he woke up at 4am. My boobs were not leaking or too full. I fed one breast and slept another 2.5 hours and my other boob still wasn't majorly engorged. I will begin oatmeal every morning but can't figure out why. I recently added a pump session in the am. I want to build freezer stash. I used to only pump before bed for his only night bottle. Any ideas/thoughts? I'm worried my milk is going to disappear!