EPIRB, maybe it is the travel agents, who don't like JetStar, but why would they be also putting people off Qantas by saying this?
The story was, that although these people may be booked on Qantas say from Brisbane to Melbourne, if say the Qantas Aircraft went U/S and there was no spare immediately available, they would be put on JetStar if they had a flight going.
This is no different to what happened for decades with Qantas and Ansett, they used to just sign the tickets over.