Well, 13 of 20 seats assigned a month and a half out is a LOT. Most business travelers (the ones paying F/R or Y/B fares) don't book trips until much closer to departure, so you can be sure as heck they'll sell 7 more seats in the next six weeks. Thus, chances are slim to none that your upgrade ever clears in advance, unless there are a lot of cancellations a day or two before departure. The best hope would be the standby list at the airport, as you'd normally have higher priority than elites waiting for free upgrades. For this you have to hope for no-shows.