Last year when I flew WLG-SYD in J (EK codeshare with QF) then SYD-BKK in F my two bags were not loaded into a Priority Container in SYD.
This was confirmed by EK ground staff after all the priority luggage had arrived.
When they did eventually arrive priority labels had been removed.
I compained to EK and received 15,000 Emirates CASA Goodwill Miles.