Not sure about the time of year as far as wind or stingers go.

While in Airle beach if kiting is your main holiday activity you will be disappointed.
You will need to launch/land were there are no people or mangroves and more mangroves plus the right tides and the right wind direction.

I am sure there would be a couple of locals that get the odd session in but they have no choice.

There are only a couple of spots worth going to and one is 40kms back down the road at Conway beach, will need the right tide along with a S/SE wind.

The other is of course Whitehaven beach (Whitsunday island), when the SE trades are going I think this spot would be hard to beat. You will need to find a small operator willing to take you there and pick you up later. Forget about the big tourist boats that go there, they will always anchor at the calmest end of the beach and when you get off the boat there are about 200 other people from your boat plus another two or three boatloads, and when they sound the horn you have about 9.5 min to get back to the boat
Do a google image search to find some great pics of the beach
The tourist boats usually land at the far end (southern corner)

I was there in oct 2003 and stayed a few nights in Airle and a week on Hamilton Island and only got the kite out for about 30 min worth on hamilton island (desperate).

I am sure if you had your own boat to cruise around you would find a few good spots but with the exception of whitehaven beach most of the whitsunday area is big hills with tides and coral to contend with it is not a simple mater of waiting for the wind every day to go kiting.

Ric