In that case, I think that you really do have to weigh up what is best for your daughter, and move her if that is what you think will be best in the long term. However, as I said before, I would be REALLY wary of putting her into a class of 9 - as lots of people have said, there are possibly more opportunities for bullying and no escape with such a small group. I looked at several schools for DS, including all of the local private ones, and although I liked the small school the best, 10 was too small - particularly as it was mixed, so there were even fewer boys. I agonised about moving one to private when the others are all in state (DH and I were both privately educated and always said that we wouldn't do it unless we can send all four), but in the end, felt that the older two were thriving in their state grammars, my youngest is very happy in state primary and so I had to do the best for the child that was being bullied and having his self esteem damaged and his long term mental health and wellbeing damaged - if that meant moving him to a happier, safer environment, then we would do so. Luckily, he's now much happier, the bullying seems to have stopped*, he's got a great teacher this year and fingers crossed we don't have to move him now before secondary.
(*I didn't really put the whole story before - my (8 yo) son went from being happy, outgoing and positive to crying every day. The bullies were his ''friends'' and although I had been into school countless times, the school didn't do anything - until I spoke to the parents of the children involved (naively I thought the school would have told them - saving me the embarrassment of telling my friends what their children had been up to) and the parents then went into school to ask what was going on, at which point the school took notice and put a plan in place - which so far is working. So although, yes, the school did sort it out, it was only when I was on the cusp of moving him and talking to the governors/parents of the children involved that they did so. If you don't think that the school you have moved her to will take this seriously and act, then I think you have to move her).