Thanks for buying the 24 week expedition plan. That plan has been used successfully by hundreds of Denali climbers and we supply it to several of the Denali guide services. I think you’ll get good results.
There are two reasons that there is no mobility work in that program. Fist is that the plan is designed to be the minimum preparation that we recommend for demanding long climbs like Denali. That means that some stronger/fitter climbers may supplement with more volume. Some, like yourself may want to integrate mobility work. Some like to add yoga. We can’t anticipate these various demands so we make a plan that will get the job done if you follow it. The second reason is that there is no one mobility routine that fits everyone. I would suggest you fine tune your own personal mobility work to fit your needs; be they spine, hips, ankles, knees, shoulders, neck.
In short it is fine to supplement this plan with additional time spent doing what you feel will benefit you. We do have quite a few videos on the site showing mobility exercises. Youtube is a great resource as well.
Good luck in your training.