Hey ikw777. I grew up in Tville and although havn't been sailing up there for ages am familiar with the weathers.
As you would know it pays to be a optimistic pessimist when it comes to the wind. June/July/August are historically the least windy months of the year in this area.
If you were to be leaving for bowen now for 2 weeks according to the forecast you might get couple light days on the water

.
Man i would try to keep my options if possible open and base your trip around the forecast which for the se trades are generally

accurate. You need those big highs sitting down south ridging up the coast. If an east coast low forms forecast next week they tend to suck the pressure/life/wind speed out of the highs, and you may get more days on the water heading south into nsw,vic. Brrrrrr S,SWesters