5.5mo sleep training + schedule issues

We have been going with it with our 5:5mo sleep training for the last month. We did full CIO after Ferber was really frustrating to him. It was awful but in a week he started going to sleep in ~20 mins with limited crying. We then nap trained which has been great- he puts himself to sleep for most naps with no crying in 1-2 minutes

However, he has never slept past 5:10 in his whole life without being held. most days he’s waking around 3- happy as can be. The split night time varies, but typically somewhere 2-4, recently trending exactly 8.5 hours after he fell asleep. He’s happy and playing for the first hour, and then cries for an hour before going back to sleep (sometimes, sometimes he won’t go back to sleep at all depending on the time). Feeding doesn’t help, he’s wide awake through the feeding and still won’t go back to sleep. If by a miracle he does fall asleep feeding, he wakes up on transfer every single time.

I’ve just been struggling to stick to any plan overnight because it wrecks our days, and this has been going on for over a month. This week, we’ve let him CIO until 5am, and then go in and hold him to sleep until 6am to get us to normal day schedule. Otherwise, he will not go back to sleep that early in the morning and then fall asleep as soon as we get him at 6.

Schedule- we’ve broadened the wake day to add more wake time and capped naps at 2.5 hrs. He’s SO tired by the evening.
DWT 6am
2.5/2.75/2.75/3
Bedtime 7:30- we typically put in crib 7:10/7:15 because he’s taking a bit to fall asleep still, even if we put in crib right at target sleep time. He cries more with bedtime than nap time.

There’s just no way my baby is this low sleep needs- 8.5 overnight and then 2.5 day? SOS we are losing our minds 😭