Sandijs;
If your upcoming goal is rock climbing based and you feel you skills/strength for this are questionable then by all means follow a good rock climbing training progression and add in some aerobic training as supplement. With your long term goal of bigger alpine routes technical proficiency is key so you do need to develop that aspect. For people trying to improve in the technical/skills area as well as develop an aerobic base for bigger mountain projects/longer climbs etc we normally recommend do this in block where you prioritize with the basic aerobic conditioning or prioritize the technical while de-emphasizing the other during the block. You can’t maximize both of these qualities at the same time so don’t even try. Alternate them and they will both improve quicker this way.
Do not get locked into the week by week plans in the book. They are meant as guideline not a road map. There is not way to prescribe what you need to be doing 15 weeks from now. The intention is to show you how training works, give some tools so you can build a plan but also the knowledge to adjust it as you move along.
Scott