Many thanks JFC.

I suspect Doomben does the same as Cheltenham. Looking at archived results for Doomben on Qld Racing's website shows there's 1010m, 1020 and 1030m sprints - Qld Racing also has details of rail positions for each meet and they all differed on the relevant dates. I was thinking of calculating speed ratings for Doomben/Eagle Farm races and this complicates things a bit.

Not all distances (eg:1350m) appear to change - I'll do some analysis for Brissy tracks and maybe report back if I haven't lost the will to live by then....