Just an update, I called the station I go to and asked them. They do use 85% year round, but i wasn't 100% confident in his response. There does seem to be quite a bit of discussion around the 'net about E70, so maybe DC isn't in an area that warrents 70% mixture.

-Fadi

1991 Mazda Miata to beat Corvettes at the track
1999 Dodge Ram to climb through rocks and brush
2004 Honda Civic Hybrid to make up for the other 2