Thanks for the replies everyone, it really is much appreciated. I'm not going into this as a complete flight novice, I'm an experienced gider pilot (which will knock some hours off the required time, note the required time, I understand it takes as long as it takes), I've done quite a bit of light powered flying over the years and I was in the RAF for 20 odd years as an avionics eng so I know aircraft and instruments, how they work, what they do etc. I was also an instructor for four years on theory of flight, nav principles and flight systems.
Now I know that all of the above means diddly when sitting learning motor skills in a powered aircraft and I'm certainly not going into this thinking it will be a doddle and I just have to tick the boxes, otherwise I wouldn't waste my time and money because hopefully it will be challenging which is why I'm doing it.
I do though think that the frequency with which you do something is an important factor in determining how long it takes to do it. I should have a little pension payout next week which will be more than enough for the PPL and ratings, so I can fly as often as they can sling me into an aeroplane with an instructor, I'm not stuck to weekends either I can go whenever. Of course I'm assuming that I'll pass the medical, if I don't then it will be NPPL as I already have the medical for that. I think the most important thing I have to take with me is confidence around aircraft and lack of mystery. I've been around them all of my adult life, now I have to learn to master the fan on the front..........