I don't believe in cycles that run as long as your running Phil, I believe you hit it for about 2 months, 5 or 6 weeeks off then hit it again.
I know a lot of guys who would rather do a long course then have a long break but I always found I got side effects if on for too long, I also started to lose appetite and felt lethargic too if I was on too long or taking too much. But as everyone is different some people seem to get away with long courses, trial and error I guess.
www.extremenutrition.co.uk