Getting rakeback when you are already a member on UB

I played on ultimate bet for several months before withdrawing my money. It has been several months since I played there because I wanted to start using rakeback programs at other sites. I would like to play on UB again, but not without a rakeback program. Anyone had any luck negotiating a rakeback deal after they had already played on the site. Is this even possible or do I have to do it the hard way and attempt to open a new account?