Thanks both and sorry for not coming back to the topic before. Planning needs a bit of time to think on it.
I decided to extend the base period as suggested by Scott
So this will be the skeleton of my plan:
8 weeks on Aerobic + 2x Max Strength (Gym workout upper and lower)
8 weeks on Aerobic + 1x Max Strength (Hill Sprint) + 1 x easy ME (climbing)
8 weeks as described in the book (week 9/16)
4 weeks as described in the book (week 17/20)