VS250 5 Nov 14 cancelled?

I was booked on VS250 to Shanghai for 5 Nov 14 (in upper class booked using Flyer Miles) and I went into my bookings online today only to find they've put me onto a flight the day before. I called them and was told the flight was cancelled (even though on their nine booking it still shows as available!). Anyone else been bumped off a flight booked via flyer miles and been told the flight is cancelled? Looks suspicious, having never had a flight cancelled ahead of time like this (i.e. not due to weather conditions etc at the time).
Jon
Jon