Next marathon: same training plan?

Telstar Man

I did Frankfurt marathon last week and up next is Paris in April. I've done 10 marathons now but never 2 so close together. I'm planning to take it easy through November but then start on another 16 week programme in December. The question is, do I really go back to building up long runs from 10 miles or so like most programmes suggest? I struggled in the last 5 miles last week and didn't do enough long training runs I reckon (only two 20 milers) so am keen to focus on the distance/stamina. Does anyone know any good programmes that work on assumption you can get up to 14 or 15 miles or so as weekly long run pretty early on?

My time last week was 3.42 but I was looking for 3.30.

DT19

most intermediate plans assume you are competent to 15 miles in any event. Look at p and d for example. 

I did London then Birmingham in October and doing London next year. Once recovered I keep myself at 15 miles then from January will just alternate between 20 and 15 milers.