Help needed with sleep. Please!

Miranda

My baby was 7 months old on 22 Sept, but was born early at 36+3. The dietician said he’s caught up so I’m assuming I can go by his actual, not adjusted age.

We are on 3 naps a day, but have a routine and no schedule. What is consistent is I try and do the first nap as near to 9am as possible, sometimes from 8:30 if he wakes really early. Today, he was up at 7:30am (unheard of usually) because he had an awful night last night. He’s recently moved into his own room and own cot, plus he’s unwell and is a reflux baby who still struggles. This morning he napped from 9:10 for 50 mins. I would’ve left him have longer. Then his second nap was 12:40 -13:40, which I capped. I was out between the first two naps and had to go out after his second. Then he was too stimulated so wouldn’t have the last nap out and about. Or sleep in the car. He fell asleep on me at 16:35 and I don’t know how long to let him sleep for. He usually falls asleep at 7. Does anyone have any advice please??