For all you people suggesting that you can properly peak with a week of tapering is just wrong. Think more long term gmd, you should have been aiming for this race 12 months in advance! 1st phase of training-BASE/ endurance...your avg speeds on long rides should keep improving and you should be able to ride for longer.
2nd phase-Longer TT's and strength endurance, keep spinning on any downhill sections whilst riding to improve leg speed and strength at the same time...leg speed is often a big decider in junior races (I am a natural masher 🙁) even if you are like me you HAVE to have leh speed.
3rd phase- Move onto Interval work 1-2 minutes hard, rest 1-2, repeat x10-20!!! Incorporate some sprints once or twice a week.
4th phase- Shorter intervals using little gears maybe uphill for 20 seconds, repeat 5-10 times. Do a few 5 mile TT's to practice for the nats course
5th phase- focus totally on the nats, do some reconaissonce (spelling bad lol) of the course and do drills that you will need for the race.
This is a very rough guide but it should work, I recommend that you race as much as possible even in the BASE/ endurance phase so you learn tactics better. A few light weights in the first 2 phases wouldn't hurt and could give you an advantage over your less developed rivals, a bit of swimming even to work on lung capacity (practice holding your breath for 6-12 strokes) and general muscle conditioning.
Lastly I also recommend that if you are in Interval/ sprint phase also do a long TT once a fortnight just incase that skill you have built strats to weaken. Also do a Long ride once a week to keep that endurance you have built...hopefully it will all come together for you next year if you use this plan. In the meantime just do as much as possible for this years race and rest beforehand!