If his mood through the day is relatively okay then although it doesn't seem like a lot of sleep it is likely okay for the time being.
It sounds like he is learning to either go back to sleep, or rest, or at least stay quiet(ish) until morning so I probably wouldn't mess with that if it was me - only that moving his nap or BT could end up with that being worse rather than better. If you leave it as it is he could get better at dozing back off after the 5am NW/EW.
With a 1hr nap and if he nods back off in the early hours and gets about 10 hrs night sleep that's 11hr sleep in 24hr and you might not be able to get more than that tbh. He has the opportunity to sleep longer if he wanted to.
Often LOs do end up with around 11hrs sleep in 24 before the nap drops and then after the nap drop might do 11hr night instead, which can sometimes increase after a while.
Have you got a gro clock or timer lights? Now could be a good time to introduce one if you haven't already. It could help him to know that it is still night time and he should go back to sleep.
I'd love to get rid of the 5.30 Wu but I've been battling it on and off his whole life so not even sure if I can get rid of it!
Mine was the same, I'd sometimes manage over a long period of time to get him waking later, say 6.30am and then the clocks would change and I'd be back to 5.30am again. I can only say for me it got better when he was older. Mine dropped his nap just over 2.5yo and I don't think the night lengthened right away but over time it increased to 12hrs which he stuck to from 2.5 until 4.5yo (with developmental disturbances around birthdays, we always get those) so he was waking later. When his sleep dropped a bit I set his timer lights so that he could read in bed for 20-30 min before getting up (that means without disturbing me).