This is the reply from Mr Jason Kerr
General Manager Racecourses | Race Course Managers
Melbourne Racing Club

"When the rail is out from the true position the barrier stalls are moved forward to allow for the greater distance covered around the turns. All starts have been surveyed and adjustments are exact so the race distance does not change regardless of where the rail is. The one exception* is the 1400m start when the rail is out 14 metres, we run 1440 metre races as the stalls cannot be moved too far forward as it is a short run to the turn. Thanks
"
* my note: this applies to Caulfield only, don't know about the other tracks, but what is important is that the distances are accurate!

I appreciate his prompt reply.
Thank you Mr Kerr.

Cheers