It looks a lot like an old English variety, Cynthia. Cynthia grows to 6 ft. in 10 years, hardy to -15F, blooms mid-season. An old favorite that is still one of the best for a strong growing, background plant. 'Cynthia' will produce a bounty of large, conical, rosy-crimson trusses. Sun and heat tolerant.
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'Cynthia' blooms in the latter part of May here in the Pacific NW.
It has larger, more compact trusses than shown with no blotch in the upper petals. I have one that is 18 ft. tall after 35 years.
My guess, and it's just a guess, is 'Mrs Furnival'.
Mike

Here is a link that might be useful: My garden pictures

My guess is some sort of Rhododendron arboreum hybrid - large plants, very early blooming and deep pink a common color. With all the rhododendron nurseries that line Puget Sound, odd selections and countless unnamed hybrids abound. If it wasn't still currently March, I'd say one of our native species, R. macrophyllum......but they would not be blooming this early, even in very sheltered locations.

btw, anywhere immediately surrounding Puget Sound is USDA zone 8 (if not higher). Sunset zones are much different and do not translate well across the country.