I have seen parents told to take children out ot the pool in swimmers. It's for health reasons not discrimination. You know your child best so what would happen if you took her to the bathroom right before she went swimming then just have her wear her swimsuit? You could take her to the restroom every half hour or so then everyone will be happy. You have 6 months to work on this, you can do it.
I had 3 sons and they were all trained during the day time by then. Good luck.