I posted about this a few months ago! I also signed up in June this year so am eligible in June 2014. I will try to find my thread and link it here! I actually called and had a supervisor call me back to clarify some of the questions I had.
She said that the benefits are calculated based on your NET income for 2013 (keep this in mind when doing your taxes). The benefit rate is 55% of your income. According to the person I spoke with, your income in the months leading up to your leave does not matter (this was interesting to me because it is in contrast to how they calculate your benefits if you are an employee). I asked what would happen if I became sick and had to stop working earlier than when my benefits start and she said that there would be no penalty and that I would still qualify for benefits in June 2014. It would be interesting to see what answers you get if you call their office. We could compare notes!