I don't think they know for certain, either. Things change. There is so much overhead involved with clinical trials.
I participated in a clinical trial for a topical unrelated to hair loss. It was a preclinical trial, before the Phase I trial, for an intial saftey assessment, as well as efficacy, I suppose. I was the first one to try the topical under the offical trial, though others have tried it as well - it was a topical used for something else before.
Anyway, I had to visit the doctor on days 1, 4, 15, and 30. You'd think that it would be easy to schedule time such that I would be able to travel just 30 minutes to see the Doctor, and the Doctor would be available as well, for those 4 days. But it wasn't, and this pushed the start date (day 0) 2 months from when I first called them.
So let's say that their criteria for "Phase II trials have begun" means that all 20 or so patients have recieved the treatment, from which point on they just have to wait. Well, that's 20 people that they have to coordinate with.
Oddly enough, it's a task just to get the damn thing going, and not just because of the science. Dennis Miller said it best - we are all just a bunch of ants with beepers. Chaotic, and it's hard to plan things and keep those plans when we do.
I hope they begin by the end of this month, but I'll be happy if they start by the end of the year. That's not too far off.