Please ignore if I am on the wrong plce but...

Been calling Diamond Club to try and book Man - Miami in business class for 2 leaving 15th Aug 2012...i really want to go with US Air or Continental. The answer is nothing is showing (although they did mention a flight from Lisbon with TAP which then disappeared)

Question is am I too early? Thought it was 11 months prior
Should I keep trying at different times during the same day? ie might seats become available during the day?

We would be coming back from Orlando on 1st Sept so guess I would have to make a seperate booking.

Again apologies if am on wrong thread or asking questions I could get elsewhere and thanks for any help