Hey Lil_T;
I hope the process isn't driving you too crazy. Yes, most environmental training will take place between your BMQ and QL3 or BOQ (Basic Occupational Qualification) training. I am an Air Force trade as a Meteorological Technician and the process is changing after this pilot BOQ course. New Met techs will have to do SQ and the Basic Air course before BOQ. We are also ALL being posted to Gagetown. So much for being Air Force :S Purple trades matter very little in the military, definitely sent to where you are needed and you will take the course required for whatever element you have to work with. When I am sent to ship I will then have to take my Navy Environmental Training.
Don't worry about what's going to happen after basic, just put your head down and focus on one day at a time, the military will do what they want :S I know how you are feeling though, I was living the "what if" life last year. "What if" I get accepted, "What if" I pass/fail basic, "What is" I make the list for this next course.... It never ends, just live in the now and enjoy yourself where and when you can.
Good luck, I hope your offer comes in soon and you get the first bit of insanity over with quickly. "Living the dream"