Split nights - 3.5 month old

[starburst1234]

Hi all, please be kind, tired FTM. Baby is 3.5 months and we've been experiencing split nights for around 10 days, which I believe is a schedule problem.

Baby wakes around 8am, has 1hr 45/2 hr wake windows and generally goes down for the night around 7pm. Naps last anywhere between 30 mins up to 2 hours, total nap time of 3/3.5hrs during the day.

Tried:
Capping naps at 2hrs max (generally only one nap of the day lasts this long)
Dream feed

What sounds off about our schedule? Does it sound like she needs another wake window around 9pm after treating the 7pm bedtime as a nap?

We are feeding once or twice in the night and I actually enjoy our night feeds, it's just when it takes 2 hours to get her back to sleep the tiredness kicks in. Prior to the last 10 days she went back to sleep almost immediately.

We use white noise and the room is dark.

Thank you!

To add: I don't think this is the 4m regression, I think we still have that fun to come, as when she is asleep the stretches are generally uninterrupted.

I'm a first time mum also to a 3 month old and my baby goes to bed quite a lot later (I am not saying my way is better/right) so I would perhaps try and have another wake window and put to bed later? Maybe worth a try. My boy goes to bed at around 10.30 and sleeps generally until around 7.45 with one or two quick wake ups for a top up of milk.

Hopefully someone more knowledgeable will come along but that's what I'd try if it was me x