I joined my first duathlon (Michigan Titanium) which is 25mi bike and 6.2mi run. It’s not until Aug 20th, but I’m trying to sort out what the most effective training plan will be between now and then. I’ve joined with a friend and would like to beat him. He’s a reasonably strong runner (2 hour half marathon, 4.25 hour full) but he doesn’t do a lot of cycling.

I’m a reasonably strong cyclist and ride a fair amount. I do (3) Indoor TrainerRoad sessions during the week, plus (1) long outdoor group ride on weekends.
Running is my weak point since my knees have bothered me in the past. I haven’t been running for a few years, but started doing 1-mile treadmill runs 3x per week to start. No knee soreness from that distance. I was thinking I’d increase by 0.5mi every 2 weeks until I’m at 6.2 miles (roughly right around the event time).
Between now and then I was thinking my plan would be:


Bike:
3x per week indoor on TrainerRoad:
“Sweetspot Base 1 & 2”
“Sustained Power Build”
if any remaining time: “40K TT Plan”
I’ll also do (1) outdoor ride per week with my cycling group, usually 50ish miles with ~3,500’ climbing

Run:
Start with (2-3) sessions per week of 1-mile treadmill runs
Increase distance by .25 mi per week
This will roughly set me on track to be running 6 miles near the time of the event.

Is this a reasonable plan to do well in this event?