4 month sleep regression help

At week 15, my baby's naps started becoming super short (20-40 minutes) but night time wasn't bad (sleeping from 8-5, and then up for the day or really hard to get back down). That lasted for a couple of weeks, and then we added in night time issues. Up multiple times per night and really really hard to get back down. Sometimes those middle of the night wakings would last for hours at a time, or he would only want to be held (not a habit I wanted him to get used to, so I have kept trying to put him down in his crib). 5 AM became the new wake up time, no matter what I did to encourage him to go back to sleep for a little longer. He has been going to bed around 730, so I know duration-wise, 5 AM is not that unreasonable, just really hard when I'm working full-time and have a toddler too and can't go to bed right away after putting him down, so by 5 AM, between going to bed later and all the night wakings, I'm lucky if I've gotten 4-5 hours of sleep.

Is anyone else struggling to get their babies back down in the middle of the night (1-3 AM-ish, so definitely not early enough to be wake up time)? Naps have gone back to usual (good length) as of a few days ago, so I'm hoping that we're on the tail end of the sleep regression (week 6 now), but being awake for sometimes a 2+ hour stretch is really hard, especially when I'm barely getting 5 hours of sleep total, and more than half of that 2+ hour stretch is just trying to get him back down after feeding and a diaper change. I don't know if this is the tail end of the sleep regression, or some new habit he is going to be sticking to. I'm doing all the usual - no stimulation, only using dim salt lamps, sleep sack, white noise, etc.

Anyone have any tips? I'm breastfeeding him. My husband thinks we should try switching him to a pumped bottle in the middle of the night to make sure he is extra full/content so he might go back to sleep. Any tips would be appreciated. I'm so 😴