America West FlightFund (Discontinued Program) - PHX-PHL Gold upgrades

Has anyone flown this route regularly? What are the odds of a gold being upgraded to first doing PHX-PHL on Sundays and returning Wednesdays?

Don't know if this helps but I got upgraded to First and the seat next to me was empty on a LAS-PHL flight last August and I was only a CO Silver Elite at the time....