I wrote an article for Blades Magazine on this very subject this year earlier this year.
Firstly , do not believe those who tell you it is best to have no flying experience before to start rotary.
If you have a PPL SEP you will have air-aware experience from Radio to cross country nav and basic airmanship disipline .
This will enable you to concentrate on the new skills to be learnt on controlling an "angry palmtree"
As already stated You are allowed 6 hours off the mandatory 45 if you hold a PPL SEP, but it is irrelavant anyway as the average hours will be between 55 and 70 anyway. Weather, time, skill etc etc.
If you need any advice you can contact me by a private message.
Good luck
Ken