Thanks everyone. Dropping the afternoon sleep is not an option. She'd be too tired for that. She sleeps for up to 3 hours in the afternoon right now. Have cut back the sleeps in the afternoon with no change at night unfortunately.
Basically the problems started with daylight savings. She was going to sleep by 7:45pm and since daylight savings started she has fought sleep before 8:45pm. So, I've just accepted it and yep, the rascal goes to sleep at 8:45pm quite readily. We'll work on bringing that bedtime back by 15 minutes a week and see what happens. Bringing it back by an hour was clearly just too much.