If you set the plan from now to 2022… it will more than likely do some combination of base/build repeat for a time, before you start the specialized… then you would do it again…
My A race is late October…
I set it up 5 weeks ago… and it gave me:
Build, Base, Base, Specialty…
If your event is far away (probably over a year away), You could start with a non specific plan to build your bike endurance and your running off the bike legs…
Alternative… since you need to work on your run, You could do a running specific program (half marathon distance probably) for 12 weeks with focus on workouts, and replacing some easy running days with endurance bike rides…
There are many ways to take on this challenge…
I would personally pick working on your running endurance… the run will be hot and you need as much running endurance as possible!
Best of luck