Murray, Welcome to G/N;s - Do you plan on spending a month travelling the GRR, or are you planning a one month trip from Qld to GRR and return?
If you are planning to stay at some of the Station homesteads - you most probably require to book well in advance, so you will need a tight schedule. We free-camped across other than a one night at Ellenbrae.
We were up that way this year and it was very very busy because of Covid. I cannot see next year being any different or it could be even busier.
I would suggest booking, you will be at the mersey of numbers.
Great trip, have fun, it will be busy no matter where you go
Ian
Be sure that you have a look at the attached web site as part of your planning.
As well as the general guide they send out regular free newsletters updating among other things, information on the GRR .. state of the road, how busy it is/has been, what's open & what's not et al.