Who's doing daytime naps if you are at work?
Because it's daytime naps and settling techniques that will sort this. It therefore needs consustancy between what happens with you and what happens during the day.
Firstly - establish loads of ways for baby to access comfort independantly (ie himself). So this might be dummy, snuggle toy, special blanket, ritualistic action (parting his stomach for example). Give hom loads. He needs lots and lots of comfort.
He's also likely to need adult comfort for a while yet, to establish trust that he'll always be comforted. But I'd do this with baby in cot and carer (whoever that is) sitting next to cot. Plenty of eye contact, care, reassurance,patting shushing, reassuring form hand on chest. Constantly lying back down and keeping hin still.
A mantra helps for routine. "Sleep time now. Lie down quietly for sleep time" or whatever.
You should be able to withdraw that parental comfort over time and replace with independant comfort. But it needs establishing first to develop healthy sleep habits.
Then your daytime.
4.30am is too early to start the day. It's going to take some hassle to change it though.
Keep baby awake until 9am if possible (this fits with a more reasonable 6.30-7am wake time. Then try to resettle quickly when first stirribg awake. Cot nap, same as described above.
Next nap after about 2h awake time and same again. Depending on the length of these 2 naps, a third nap may be needed after 2 hours awake time again. Aim for either 9-10, 12-1, 3-4 naps or 9am-11am, 1/2pm-4pm naps.