Look at Physconia detersa. It’s close. It’s supposed to have continuous soralia along the margins, but Brodo mentions a species I’ve never heard of, P. leucoleiptes and claims it’s “marginal soralia can become crisped and broken up into individual more or less lip-shaped soralia”. Very promising.
I think both Physcia and Heterodermia would have much paler gray color (atranorin). And the rhizines wouldn’t be as dense (you can see a fringe of them poking out from under several lobe tips). These look more like Physconia or Phaeophyscia rhizines to me. The pruinose, concave lobe tips strongly suggest Physconia to me. Besides, I think you’ve about exhausted the Phaeophyscia in your area already! :)
