They billed me a week or so before I received my approved itinerary in the mail so I'd say it sounds promising for sure.
Considering that they have the following on their website, I'd say you lucked out:
May 14, 2013: Attempting to reserve camps to hike the entire Wonderland Trail, or a large part of it, is no longer possible for trips starting between July 13 and September 25. See the FULL CAMPS list below. The number of applications for the Wonderland Trail are unprecedented this season.
I'm going the first week in August. When are you going?