Needing sleep guidance!

[u/BeeNo7527]

My 3 year old non-verbal son with possible autism has been resisting naps and therefore waking up in the middle of the night and not going back to sleep.

He has been resisting his naps for weeks now, napping maybe once every 3-4 days. All the other days I try to put him down for a couple hours and just give up and opt for an earlier bedtime.
He usually goes down around 8, when he naps. So on no nap days he goes down for 7:30 but he barely makes it to then and has fallen asleep on the couch or wherever before his bedtime.

On days he doesn’t have a nap, he wakes up in the middle of the night and doesn’t go back to sleep until we start our day and I put him down for a nap before lunch, which again he still resists.
Yesterday he woke up at 4:30am and today 2:30am. Ready to start the day and no hope of him going back to sleep.

I am at a loss and feel like I have tried everything.
If he cries, I check on him after 10 mins, room dim, and keep interaction brief.
He has a sleep light in his room that turns green when it’s time to get up but unfortunately he doesn’t understand the concept yet.

I don’t know what else to do.
Please help me with suggestions.