Has there been any news on how the GUC standby list prioritizes customers?

I just called DL and she said Diamond MMs get priority over normal Diamonds. The next tiebreaker is AMEX Delta reserve, then the next tiebreaker is fare class and time of booking.

This is my first time hearing MM status makes a difference. I do not see this documented anywhere on DL's site.

I welcome any clarification or insight into how the GUC standby list is prioritized.