Don't do the GA ready course, you already have a licence, those guys are just there to pinch a few extra dollars, have a look at the thread, "What happened" that's an experience of GA readiness that you need, maybe bring your own pineapple to sit on for the next few years- remove the spikes.
As for moving up, I would say, no time like the present. Definently before wet season starts, for your own safety and the companies they would want you to be semi comfortable in the plane and to be making correct judgement calls on where your limits are.
But don't just expect to get a job, shake a tree up there and a junior pilot falls out- bring knee pads and your own gag ball- really show you want to go the extra mile..
