10 month old sudden sleep issues

I have no idea what has happened but my baby has just turned 10 months old and I feel like he has forgotten how to sleep! wondering if this is a regression or a schedule issue? if it is I can’t seem to fix it!

Hes always been an up and down sleeper - awful awful as a newborn then slowly got longer stretches. I used PUPD around 6 months and was happy with where it got us to. he mostly self settled with occasional rocking but I was happy with this as his sleep was good.

once we changed to two naps I put him on 3/3-3.25/3.75-4 wws and he started sleeping through the night a few times a week which was amazing, if he didn’t sleep through he’d usually have one or two quick resettle type wakes.

last few weeks it’s gone crazy, I can’t get him down, he pops back up awake, he needs rocking but won’t settle on me! cries when I leave. or just plays in the cot. bedtime is exhausting then he’s waking multiple times in the night, sometimes for a few hours at a time (but he’s tired and wants to sleep - hes not playful). its now crept into the naps and it’s taken me soo long and some tears from both of us to even get him asleep at all today and he’s popping awake after 30 mins.

has anyone else experienced this and did anything help? I’m so stressed we’re in an awful over tired cycle now. or is it a case of wait it out and see if it passes… I feel like back in newborn stage and its getting me down!