A.S.
Personally, I think cold turkey is the worst approach. I know some peds recommend it, but most peds know very little about BF. Doing this cold turkey is traumatic...she has know BF all her life as her comfort and her source of nutrition...to suddenly just take this away from her is kind of traumatic. I would imagine it is hard for you too.....uncomfortable and emotionally difficult. Also there is no reason why you need to do it NOW. If your daughter still enjoys it, and you are ok with continuing with it, there is nothing that changes at 1 year that makes nursing suddenly not as good for your child. I don't know your situation...whether you did it cause you wanted to or if you were pressured by someone, but just know that if it wasn't your idea.
It would be much easier to just cut down one feeding and go with that until she is used to it, then try cutting another, until you are no longer nursing. It will be a gradual adjustment for both of you...you won't be sore and upset (and won't have to pump) and she won't be upset either.
As far as when you stop producing milk, it is different for everyone. Some Moms still have some milk months and months afterward. My breasts did not return to their previous size but I also had gained some weight. I think usually most women get at least close to their old size.