I get back from NTC beginning of July, and there is a Norwegian Ruck March on September 14th. I have roughly 2.5 months to recover from NTC, rebuild my base, and prep for the march.

I'm not new to running long distance, as I run 10-12 miles every Saturday, and average about 30-35 miles per week on my own time. Additionally, my last 12 miler was a 2:42, averaging 13:30 per mile with 35 lbs. The Norwegian Ruck March requires that I ruck 18.6 miles at a 14:30 pace with 25 lbs. For my other cardio, my last 2 mile was a 13:49, and my last 5 mile was a 38:31. I also squat 335 and deadlift 405, and max the plank on the ACFT, so I am not concerned about my leg and core strength for rucking. As it stands now, I can walk a 13:30 with 35 lbs for at least 4 miles with no issue, we haven't gone longer than 4 miles for PT.

I recognize that Green Protocol has a section that perfectly covers this. However, I will be at NTC for roughly 7 weeks and will need to rebuild my cardio base. Since I have 2.5 months to recover and prepare, how would you attack this problem? Considering it's only 25 lbs, closer to 35 with water, would you recommend I do more long-distance running than rucking? I can more quickly build my running base than my rucking base since running is less stressful on the body. The last time I did a ruck (12 miles w/35 lbs dry), I hadn't rucked for 3-4 months prior, ran maybe 15 miles a week, and managed to run/walk it at a 13:30 average pace.

I would appreciate any help you can provide.