JMT Permit Startegy.

I am from Minnesota and I am planning a JMT thru hike in 2015. I am still flexible on the month to hike but prefer early September. How difficult is it to rely on getting one of the 60% reserved permits and is there a better way to fill out the application? Such as bracket the start dates within a week? Hiked the Wonderland around Rainier and went counter-clockwise starting at Sunrise and the camps seemed more available because of this strategy. First things first, get the permit and then plan the hike.