Thank you all for your reply.

Virgin Australia has a earlier flight from SYD but what Delta told me was that if we ended up flying coach that segment , they would refund some miles. They did not offer the earlier flight as an option even though i asked for it.

We were originally booked in a 737-800 with Business class available. NOw the flight will be a 737-700 With no business class. The flight is in November on a Sunday and looks like V Australia does not use the 737-800 on Sundays to Cairns during that month. At least is what a res agent told me.

Davisew, can you give me a link where this topic was discussed? What is AFF??

Thanks