Thanks for all the comments about feeds - really helpful.
The cold seems to have gone, and with it the night wakings (hurrah!!) so I've tried stretching her longer in the day between feeds and she seems fine with it - in fact, I'm not sure she's even noticed! So, we've had a couple of days where we've fed at 7, 11, 3, 6.30 and then the DF at 10.
It went a bit wrong yesterday as she work early and fed at 6.30 and so couldn't last the extra half hour, and had to sneak in an extra snack in the afternoon to keep her going till bedtime, but hopefully once she's used to the 4 hourly thing, she'll be able to accomodate the odd day where one gap is 4.5 hours, and we will be able to stick to 5 feeds a day. Leaving the DF well alone for now till this arrangement had bedded down a bit.
As I'd hoped, now the cold has gone she has renewed enthusiasm for eating so we are now managing 3 meals a day. She's still not actually consuming a huge amount but is definiftely more interested than she was so that's a step in the right direction too. She's also getting MUCH better at eating simple things (banana, biscuit, avocado etc) without smearing them everywhere. So maybe the time has come to start on messier stuff like pasta and sauce. I, too, don't really want to waste time cooking for her till I know she's going to eat enough of it to be worth bothering with, though!
Great idea about the 2 layers of bibs ... why didn't I think of that?! Thanks, Pauline.