When/How often does your 9 m.o. nap?

[blackcurrants]

DS used to be a regular, every-2-hours for 45 minutes chap. Then it stretched out a bit and settled at 3 naps a day. His day used to be used be at
6am Wake
8-9am: Nap for 45 minutes
11am-12noon: Nap for 1 1/2 hours
3-4pmish: Nap for 45 minutes
6.30-7pm: Bed.

NOW it looks like this:

6am: wake
8-9ish: nap for 45 minutes, sometimes a 'double' nap of 1 1/2 hours happens now.

11am-noonish: nap for 45 minutes

then be WIDE AWAKE and INCREASINGLY GRUMPY all afternoon, refusing to nap at all, until a rather rushed and crabby supper and bath and bed.

He's recently learned to crawl, pull himself up, and take steps (all in about the last 3 weeks) and so when I put him down after a nice calming breastfeed, into his cot - he often crawls straight away and pulls himself to stand and is screaming before I've even got out of the bedroom.
I've tried leaving him but he often bawls for 15 minutes or more (20 is the point of no-return for me, if he's really tired he'll sleep by about 11mins) and when he's standing he can get back down so just cries for ages.

Argh. Is this when they drop a nap? I can't believe he'll do from 1-2pm to 7pm without getting overtired, but he doesn't rub his eyes or yawn, is just a bit clingy...
this is a huge post, sorrry! Is this happening to anyone else?

Mine does

6am wake-up
9am-10am nap
1-3.30pm nap
7.30pm bed

I'm trying to move the morning nap to 10ish and limit him to 45 minutes though in the hope he might sleep in til 7am

When ds started standing up in his cot and crying at 8 months I stayed with him and just laid him down everytime he stood up (kind of a modified Pick-up/Put-down). Cue an hour of screaming (this was during the night) but it seemed to sort it.

DH has been doing some 'help-him-lie-down-and-pat-him' (just now, in fact - and it worked!) so I think that's going to be a feature - thanks for your suggestion!

I really need him to keep that afternoon nap... but I suppose there's nothing I can do about it. Argh, babies do keep on switching up the rules, don't they!