Hi there and welcome to BW forums.
Around 9mo is a really tricky age for sleep as there is a big developmental leap around now, seperation anxiety kicks in, sometimes changes to nap routines & often also teething. Even when babies have been sleeping well & self settling previously,sleep can get very disrupted at this age anyway.,. Hence the "8/9/10 month sleep regression"
So it might not be anything you're doing "wrong" but just part of the stage she's at..It sounds like you're doing what you can to get through without re-establishing the feeds or rocking that you've worked so hard to fade out.
My DD is 10 mo and we have just had a fortnight of dreadful, long night wakings. When my DS went through this, he went back to normal after a week or so on his own. My DD seemed to get stuck in a habit though and I had to use walk in/walk out (next step on from PU/PD) to eventually get her sleeping better again.
So ... Your DD has slept through so what you're doing for sleep training must be working...so could there be another reason for the wakings?
Teeth? Seperation anxiety? Working on new skills? Routine changes or need for one?