5-8times a night! Wow you must be exhausted, you have every sympathy from me. I'm really tired with only 3 NWs
What is his daytime feeding like? I.e. How often & for how long? Do you think he's getting enough in the day? Could be a habit of getting all nutrition at night & not enough in the day?
Maybe it would help to post his daytime EASY routine to see if anything needs tweaking there?
I agree that working on independent sleep will probably be answer (it was for my my DS when he woke frequently at night at 4mo) but need to ensure daytime feed & nap routine is getting enough milk & sleep for a good night.
FWIW PU/PD didn't work for us. I needs to use a gradual withdrawal approach to weaning off feeding to sleep xxx