Reflux is something I do understand
. Plenty of BTDT experience with my DS - and he isn't the best sleeper either
.
What I think is that he is hungry - but only because he is used to eating at that time and has spaced his calories over the 24 hr period rather than concentrating them in the normal 12 hour daytime period. It probably is a bit of a hangover from his reflux days really - but a LO weighing 20lb and eating well during the day really doesn't need a night feed.
I would go ahead and start diluting that feed. I did it many times with my DS (after his reflux flared and the night feed came back). You can go as slow as you feel comfortable with. But start with 7oz of water and 6 scoops of powder. That way you have reduced the calries and hopefully can add those on during the day next time. I used to reduce every 3 days or so.
See how this method goes. I found DS didn't bother about a taste difference until it was less than 50% formula - and by then he was less hungry for it anyway.
Some LOs do feed in the night for longer - but they are usually eBF.
What do you think?