It's certainly been done before. My advice would be to try and find out where and see what the possibilities are in the future. It may not be wise to inform the cc selectors of your intentions and indeed CPL qualifications............
It could certainly prove to be a valuable networking resource. Just think of the management pilots whom you would have access to during stopovers/turnarounds etc. to engage in conversation and possible 'get on board'.
I do suspect the reality is that you would have to jump through all the same hoops as anyone else, but it may get your application looked at. Question is, how are you going to improve your pilot CV in terms of hours etc if you are working full time as cabin crew...........just a thought.
Caledonian certainly got their fingers burnt a few years back by sponsoring one of their cabin crew who ended up taking an extremely long time to pass all the training, and a lot more investment (which kept coming in an attempt to save face) and then they ended up with a product that they were not completely happy with. I know this is different from your situation as you are not looking to be sponsored, but I thought it interesting.
Good luck
PP