Ours are okay at the mo. Apart from me finding myself asleep in the sofa hunched over the laptop in the wee hours.

I remember that around 10 months I got into a real messy OT UT cycle with DS. For the same reasons - a rough night without good sleep and he couldn't do a decent am A time. Our days generally stretched a lot for several months too - I think some days would last 13.5 hours thanks to EW and attempting to squeezing in the naps with a long enough A before bed.
I found, with Sherry's help, that I had to closely watch DS's behaviour, keep a sleep log (even if it's just in your head) and sometimes be brave... so what I mean is that when you 'know' they've had a good hit of sleep at night (say 11h) but are showing tired signs after 3h, then I'd push it a little because I 'knew' he'd had good sleep. Other times, I'd watch him closely for any hints he was ready for his pm nap, as he didn't show any signs at all - I'd put him down for a nap and he'd resist for hours as OT. Grrr...
I started cutting the nap times at 9 / 10 months. At 10m I knew that he wouldn't sleep well if he had more than 2h15m (or maybe 2h30m) total day sleep.
It is really hard doing the switch. I felt obsessive!!!
Jane: we only ever go away to stay at my folks. And that is now a nightmare. DS used to sleep the whole journey happily so I always drive at night. Now, he doesn't sleep - even when it's dark. Car lights I guess. So he's awake most of the 5 h drive. Then when we're there, I really struggle to get him to nap or go to sleep at night. He won't independent sleep there either. It is a huge cotbed in a cramped room, with a bookcase overshadowing it. I think that doesn't help. He's used to a cot against a wall with a clear view of the whole room and, importantly, the door.
I'm down there for 5 days next week. Hope to sort the sleep somehow.
Hope everyone's nights improve
Charlotte