As I've discovered, it's difficult to find out who's who in the LDP records dept. I was advised to try 'Martin Stone martin@sportident.co.uk who is the FRA record-keeper for that sort of thing', but he's a busy man, so don't expect a speedy reply (if any) - I didn't, but if there is, I agree with Tony, it will likely be in the region of 48 hours.
I planned the route solo for five days (that elusive 5 days!!!) thus: Chepstow, Pandy, Knighton, Forden/Welshpool area, Llangollen etc..
But 2 months puts you in December and very short days, so if soloing it may well just be wishful thinking! On the other hand, it just might be possible with a theoretical 36m a day - but don't equate those miles with road miles!
With back-up in the tradition of the fell runner it's a different matter of course.
But I for one would certainly be interested in your plans and progress.