First question - choose the one feeding that will be easier to wean first. Change your routine so that the feeding is just kind of skipped. If you lounge in bed and nurse her in the AM, then be up, get her up, get her dressed, go to her playroom and start playing, get her breakfast right away, etc. Just make sure you don't linger where she normally gets her feedings.
If you nurse her right before putting her into the bed then change the routine, read books on your lap instead of nursing then put her in the crib. If she nurses earlier in the evening then just skip it and move onto the next step.
I had to wean my 2 yr old due to fatigue from pregnancy. Simply not being around helped (I went to bed before he did). The AM feeding was the hardest, as my husband was already at work, but we just got out of bed and went down for breakfast before going back to his room to get dressed. It all kind of worked out.
Whenever he did ask to nurse I just told him that they were empty and there was nothing left. Then told him we could cuddle and read a book or go play with his toys. I have noticed that the main times he asks to nurse is when he is getting tired or hungry - so if I address those needs it helps.
Also, just keep yourself moving, if you don't sit and you are not accessable, it is harder for her to nurse.
I would also wean one feeding for a month or so before weaning the final time - you'll be able to tell her when she asks "Remember we nurse only in the mornings now". Knowing it would come again later seemed to help my son. When she is "comfortable" with only the one feeding then you can start to wean that one.
Hope that helps -
Second question - Is the sudden wake up from the time change? If so, then just keep putting her back to bed for half an hour longer so she gets "used" to staying in bed.
At about that age, we got my son a digital clock in his room. We taught him what the 6 looked like, and told him he could get up when it was 6:00. If he got up earlier we reminded him he had to stay in bed until 6 - then left him. He still (at 2.5 yrs) will get up earlier, but usually we can tell him it's not 6:00 yet and he'll go back to his room and wait (man I miss the crib for that reason :-)
She might not need as much sleep, but there also might be something new that wakes her - I'd first try keeping her wake up time as boring as possible (even trying to keep her in bed) and see if that helps her to start sleeping later again. If it doesn't after a week or two, then you might need to adjust bed time. Good luck
State Certified Early Childhood Special Education Teacher
New Mom as of March 2009!