But it's more good news and mediocre news; 540.8 miles on the tank was an all time distance record for this car (maybe any car I've owned), but at 10.064 gallons to fill it, that's only 53.736 mpg.
So, I dunno. I don't think I totally lost all hypermiling ability. Maybe the "new" tires? - - and I wonder if they're switching to "winter gas"? Oh, I got gas at a different station - different company. Hmmmmmmm....