One issue with the OP's protocol is that 30k is going to be a total threshold (1-hour sustained power) effort. You need to tap into that zone in your warmup, and if you're at 80% of your max heart rate (assumption by me), you're most likely well below that. Here's one that I've used for a couple of years that has worked well for me:
20 minutes easy
10 minutes low tempo, just a hair below where your 80% would put you 80 rpm
2 minutes easy
6 minutes ramp up from low tempo to threshold 90 rpm
2 minutes easy
2 minutes above threshold, (90-95% max hr) 105 rpm
2 minutes easy
2 minutes above threshold, (90-95% max hr) 105 rpm
2 minutes easy
Ideally you time it so you finish up within 5 minutes of your start time. You should have all your crap together before you start your warmup to you're not frantic trying to make your start time.
Here's another one from O2Endurance website:
WARM-UP SCHEDULE FOR MID-DISTANCE
20 min. EASY ON THE ROAD
10 min. at ZONE 3 (ON WIND-TRAINER)
1 min. at ZONE 1 (ON WIND TRAINER)
5 min. at ZONE 3 (ON WIND TRAINER)
4 min. at ZONE 4 (ON WIND-TRAINER)
3 min. at ZONE 2 (ON WIND-TRAINER)
2 min. at ZONE 5 (ON WIND TRAINER)
After trainer warm-up, go to rollers
5 min. at Zone 3 (100 rpm)
2 min. at Zone 4 (120 rpm)
5 min. at Zone 2 (100 rpm)
Off rollers & directly to start line!
I wish I could find the one Team Sky was using recently, way simpler than either of these.