I understand your concern about a nap of 1 hr 30 mins, but can assure you that he will lengthen that one nap as long as he has enough A time before you put him down... I would start by pushing for at least 4.5 hrs A time in the morning.
Thanks Kara, that makes sense. Do I stretch this A time gradually or just go for it? We were having a bit of time where he could do 4 hrs, but then when he did sleep it was only 45 mins, so by the end of the day he was shattered.
My concern about doing EBT in that situation is that he may wake earlier, then bringing the 4 hr A earlier in the day, meaning that either its an even earlier BT, repeating the cycle, or he needs another sleep to get him to BT.
That said, I'm not totally sure that he's ready for 2-1. I've gone back to 2 sleeps from yesterday, just to get some evidence to see exactly when he doesn't want to sleep, and am taking it from there.
I was so tired of fighting him to do something that I didn't really understand (have ordered the Toddler book, so with that and you lovely people I'll be more prepared next time!), and was getting cross with him for not sleeping 'properly'. Maybe he's just not ready. He did 3-2 transition like a dream, he just stopped falling asleep around 4.30-5, and wasn't bothered by that longer A time before bed.
Don't want to feel like I'm giving up on him, and can't bear thinking that I might not be doing what's best for him, but I've got to listen to him too right?

I hope so!