The Brisbane supply of Caltex Vortex 98 appears to be getting back to normal. The recent shortage was due to a misshap at the Caltex Lytton refinery. I believe this refinery also produces BP's Ultimate. I prefer to use these two fuels. I had to fill up with Mobil 8000 over new year as it was all I could get locally. Initially I was a bit worried (getting out of the comfort zone), but can report that performance seemed the same.