Implications of Registering for GST

Noob Question!
I created an ABN couple of years ago to by .com.au domains , but never ended up building those websites. I do intend to build them at later stage, but would have no revenue under that ABN for another year or so.
1) If I haven't earn anything under ABN, do I still need to do anything at the tax time ? I currently file tax return under by TFN
2) I am planning to sign up ABN for GST - this is mainly to take advantage of Qantas business rewards (I take 2-4 flights a week, this will save a lot of money as booking via Qantas business rewards has cheaper tickets and more points). Would this have any imopact on 1

 

an ABN is just a number, it doesn't really change any tax implications, but you are probably not entitled to one if you are not conducting a business. The ATO may cancel it after a while.

If registered for GST you would need to charge GST on supplies - if you are not earning anything this won't matter as you are not supplying anything. But you would be required to lodge bas statements.

 

Thanks Terry. That's exactly what I was looking for.