I guess management knows the numbers for next financial year are...

I guess management knows the numbers for next financial year are going to be good, hence the buyback.
Management wouldn't be announcing a buyback if they were not confident of money coming in through the doors. Would have taken a lot of analysis on future and long term cash flow by BET management and Barrenjoey team before this sort of decision is made.
Even 80 million of share buyback at between 40-50 cents a share is approx $32 - $40million which is a big amount for BET.
Overall a good decision by management to rein in SP going south and keeping short sellers at bay.