How's Kiwi today?
Well, although I myself don't care for the birds that my store sells, many of my co-workers/friends have LOTS of experience with birds, of many breeds and sizes, and have seen many ailments and after a visit to the vet many cures in their years of experience. I went ahead and asked a few of them if they have any input and/or advice. I told them everything you told us, so, I told them all I know.
I'm guessing nothing in her cage has changed recently, like a new nesting box or toy? Or a new type of food or treat? At any other time it may not be a problem, but while brooding even the smallest changes like that can cause excess stress and lead to self mutilation. If by chance she is getting a new food or treats, maybe she's allergic to something in them. But after 10 years experience, I'm sure all this has come to your mind already. And I told them that, but I think it's worth mentioning, just in case.
Have you put anything extra soft like polly-fil or nesting material in her cage to give her some "comfort", so to speak? Not only will it give her something soft and warm to cuddle against while she's feeling odd, but she might also take her frustrations and stress out on that instead of herself. So that might help. Hehe, I told the girl who suggested that (who is also the supervisor of the bird department with probably the most experience) that you sew, so you should have easy access to some, if not some on hand already.
As to the irritated preening gland, it's mainly because there are no more feathers there, and she's stimulating it a little too harshly without the feathers there for buffering.
All the people I talked to said it's normal for small parrots to go through bouts where they pluck all their feathers, moreso even than larger parrots and smaller birds. Only a vet can find out exactly why and instruct you how to fix it and/or give you something for it, but it's usually nothing to worry about. So try not to worry. Maybe you've just been lucky over the last 10 years if she hasn't really done this before. That shows signs of a happy and healthy bird.
Hope she does ok until her vet appointment. And hope they're able to find out what's wrong. They may put a funny collar on her to keep her from plucking her feathers, but hopefully that'll be it.
Feel better Kiwi! And hang in there Sparky!
