I’m glad to hear that you are seeing rapid progress in endurance. That’s a hefty day by any standard. Nice work.
With your strength background you can and should drop the max strength. I’m sure you have more than adequate general strength. It would be a fine idea to substitute more climbing specific strength in the form of bouldering and or hang board etc. And finishing that workout with some single leg stuff and general core work is a great idea.
Many folks transition from running to skiing in the winter. Skiing will build a lot of up hill specific endurance. If you can keep 1-2 little runs a week it will help with the transition back to running in the spring. If you have access to nordic skiing that too is another way to keep building that aerobic base. You’ll be able to handle a higher volume of this aerobic work than running too because XC will not beat you up as much as running.
Sounds like you are off to a great start. You can just keep in the base period as long as you want. You can’t have too much base. And the bigger it is the more/harder of the event specific training you’ll be able to manage when you do find a medium term goal.
These little steps that you are now taking will accrue over time to take you to those 8000m peaks. Keep up the good work.
Scott