jenni yay for the extra long sleep. In fact Will did exactly the same on Sat night, and I persuaded DH to take him after his 6:30am feed until he needed another feed at 10 so had a lovely lie in and an extra long shower.
Re the super short day time naps: I've become unhealthily obsessed done a bit of reading about sleep patterns since Will's little regression last week. He's always had one long nap of 1 and a half to 2 hours during the day, and then 3 30-45min naps, but was often quite grumpy on waking from the shorter naps. According to most of the resources I looked at, the reason lots of young babies wake after 30-45mins as this is the length of a sleep cycle for them. Supposedly, for the majority of babies a decent nap is 2 sleep cycles, so if they wake after one you should try and resettle them. Obviously, if they've woken because they are hungry then they won't resettle and you should feed them.
I've been trying this approach with Will for a whole 36 hours now
and he does actually go back to sleep for an extra 45mins if I resettle him when he wakes. I've always managed to get him to take his longest sleeps when I'm walking with the pram, and he does actually wake after 1 sleep cycle then drift off again by himself, so my new morning routine is to pop him in the pram once he seems like he needs his nap and to walk for 1hr 15mins, to ensure I'm home 15 mins before he wakes for a feed. So today I'd walked 6km before 10am
He's currently on nap number 2 - he woke after 45 mins, and he resettled pretty easily with some rocking and singing. Putting him back down was not so easy, took about 20 mins for him to be put down and stay asleep, but he's now fast asleep in his moses basket again. I'm impressed with how easily he went back to sleep - I'd already decided I wasn't going to fight him as I think he'll eventually get the idea by himself. I'm hoping that by helping him get better quality sleep in the day, he'll be less overtired and irritable in the early evenings.
I'll update with our progress in a couple of days 
If it works I might just become a baby sleep guru myself. I could use all the new found nap time to write a book full of my expert advice and make millions 