Keep in mind that DL has been offering many promotions to travelers based in SEA to earn status more quickly, so on top of all the reasons others have mentioned as for why this upgrade is unlikely, if there are any op-ups, GMs are at a disadvantage here since there are also going to be a greater share of PMs and DMs on this route than might otherwise normally be the case since SEA travelers are racking up status faster than others (and travelers who fly to Asia regularly rack up status faster than anyone, other than those who are getting MQD-ed out).