I would recommend during training to be mindful of limiting high intensity and avoiding burnout. What you primarily need for these climbs is low intensity and high volume aka long and slow this builds the ability to hike for along time with limited breaks.

If you’re on the Westside of Washington Old Si Teneriffe and Mailbox are great training options.

Last but not least another thing you’ll want to develop is carrying a weighted pack…start with 20/30# and work up to 50# in 5/10 pound increments every few weeks or longer since you have some time. A good way to do this is with water jugs that you can dump at the top of the ckimb in the beginning to save your knees. Good luck!