Weird schedules affecting baby’s sleep

Hey guys. So when our baby was born, my husband’s ship was in the yards and he was about to transfer to a new command. He took his paternity leave, then went back to work for two weeks (super normal hours) and then took transfer leave, and then was in school (again, super normal hours.) Our baby has always been an awesome sleeper (only waking to eat every 2-3 hours, but not fussing, and sometimes going a 4-5 hour stretch once a night) until now. Baby is now nearly 4 months old, and my husband recently started his new schedule and the hours are all over the place. Some days he has to be up at 0030-0100 to make it to work by 0230, others he gets home at 0300, some days he works only during the day. The times when he has to be up or gets home in the middle of the night, the baby wakes up because he’s moving around and has a light on and everything, and now our baby has been sleeping horribly. As I write this, it’s 3am and baby and I have been up since 2330 when my husband got up. Nothing I do will get the baby back to sleep, and I’m losing my mind. I can’t take 3 years of this awful schedule 😩 Does anyone else have a young baby and room share and their spouse/SO works weird night time hours? How do you get your baby used to it/get them back to sleep if they wake up when your spouse/SO leaves or gets home? I don’t want to ask my husband to sleep in the guest room on the nights he works because that would be fairly often, but somethings gotta give because mama needs some sleep 😴 and lord knows I’m not getting it during the day.