Officially on Twitter (according to HRV) is due to state of the track, inclement weather and after both the HRV and club mobile could not gain traction. Decision made 20 minutes before the first.
Given there are no Victorian races on today, am sure they would have given it every possible chance turnover wise. Wonder if walk-up starts were thought of?
BTW, here is what happens when the mobile has a problem. I still also remember the day the mobile went off the outside of the track at Kilmore and disappeared down the bank!
https://www.youtube.com/watch?v=vCcJPqMpBi0