I'm not sure if its poss to give them too much? My friend's health visitor recommended waiting until 7 months before trying to drop any milk feeds. I don't give milk at meal times now, I've kind of split it up so she has milk an hour or 2 afterwards. This seems to work better for us, then she is hungry at meal times, and hungry enough to have enough milk later.
How's her weight doing? If its still going along at the same rate, I reckon you're doing just fine to be honest. Have you mentioned it to your HV?
Phoebe is over 6 months now, has 3 meals, 2 of which she has a 'dessert.' She still has 4 bottles of 6-8oz. She loves her solids and now doesn't have so much interest for milk.
Maybe try increasing how much she has for lunch or dinner and see how you go? Phoebe eats quite a lot compared to other babies, she has a whole Annabel Karmel ice cube plus a yoghurt, or half a fruitapura afterwards. My friend's baby just about eats that at 8 months!
At her age generally she should be able to go through the night without milk... If it starts to happen more regularly, I read the best thing to try is give them water, then they don't associate waking up with milk. Whether it works or not is another story
She could be having a growth spurt though. Very confusing isn't it!
Hope I might have helped a bit... my post re-reads a bit rambly sorry!