I don't know, Qantas seems to have done their research before endeavouring on such a costly project- and I can imagine that there's indeed a market for these non-stop flights. I myself would always prefer having a stopover so this will be a once done as a bit of a novelty (holding out for Paris or Frankfurt rather so that gives me some time to save the $$$) but I was surprised how big a success those PER-LHR flights seem to have been.
So, in short, I would be very surprised if the whole thing was now suddenly canceled again. But you never know, crazier thing have certainly happened.
