You could go even earlier - my LO is 14 months and still has his morning nap 2.5-3 hours after he wakes up. Granted he's not spirited...
but you could try giving it at 10.30 or even 10. Nothing to lose, right? Let us know how the watering down feeds goes. How have you been settling her, do you do PUPD or shh-pat? If she wakes more, I would try settling her without feeding, definitely don't do any more feeds. If the watering doesn't work, you can always go cold turkey. Yes it will be a painful few nights but she'll adjust.
