Rather an interesting on this. I think it all comes down to a blanket ban by the airlines against using any or all electronic devices.
I just spoke to an operations manager of one of the ground handling companies and posed this very scenario to them. They said they are not aware of anything written into the Qantas manuals but they always
assumed that to be the case.
Reminded me of one of my favourite lines in Lock Stock and Two Smoking Barrels "Assumptions being the mother of all fcu*ups:
Perhaps nitpicker, you would be better directing your inquiry direct to Qantas. I'm sure we'd all love to hear what comes from the horses mouth.
as for the QF vs 717 argument. Correct me if I am wrong but the crews are all Cobham, the tickets and flight number are QF, the ground crews are local companies and the aircraft a leased from some offshore owner.