My heartfelt sympathy. Our DS was a terrible sleeper. Coping with the sleep depravation was so hard, especially as I was continually trying to hide it at work and from others I just knew would be judgemental. Until someone has been through it with a non-sleeper, it is hard to truly understand.
All I can do is hold out hope - it will resolve at some stage. Hang in there.
Is he able to tell you why he is waking? Hunger? Loo? Cold/hot? Missing you? Maybe slightly later bedtime?
So difficult as even if speaking well at that stage, conversations tend to be a bit surreal 😂 (got to laugh, I know there times I could have wept).
Is he sleeping long at 9.30am, so he is getting to make up for it? In which case, you know you've got to break that cycle, maybe with a really on the go day, big dinner, supper of porridge, quiet wind down (books, no screens) and as little interaction during the night as possible
Easier said than done, but all best.
With hindsight, I battled with DS over sleep. With our next I was so tired I just got in beside them before they woke up too much and slept together - people will probably judge - but I wish I'd just done it with DS too, time together when little is precious and they learn to sleep on their own eventually.