For tempo then, i would suggest a bit more circuit based workout - ie
run 100m (jog) - 10 push ups, run/jog 100m squat jumps/burpee/lunges etc, run 100m - sit ups, run 100m step ups.
Then rest n repeat for say 1min.
You can do Whatever exercises you want - mediballs, jumps, plyros - and inbetween you’re doing low intensity tempo runs.
It gets the heart rate going, But soooo much easier than 3 x 300m tempo pace on your legs.
Plus, saves a heap of time - Tempo and Circuit training all at the same time.
Re - John - i would do the 3rd HI day Weights after 1month of doing 2 for this reason - that HI weights is easier than HI Track. If HI weights knocks him around, then he simply pulls the plug on 3 HI days.
HI weights would be something like, 1 arm dumbbell snatches, power cleans, heavy benches, heavy deadlifts etc.
Plus - i believe RB is doing Football this coming season?