Identification: Tall fiery red rhodo, blooms in April; leaves have no indumentum

Well, the Park Board did not include this beauty in their https://vancouver.ca/files/cov/ted-and-mary-greig-garden-50-rhododendrons-of-interest.pdf document - at least it doesn't seem to match any of the descriptions. The only one I can't rule out from the descriptions is R. x 'Jean Marie de Montague', but the petal edges are not frilly enough. I'm not sure I remember exactly where I saw it - it might be off a path or two north of the Grieg Rhododendron Garden in Stanley Park.

I don't really expect to get a name for this. That's fine.

 

'Montague' is more of a cherry red. A common name for it is Mother's Day rhododendron because of it being in flower at that time. On another subject note the cross sign is typically used when given names of specific crosses are stated and not when individual cultivars with a parentage that does not have its own separate name are being mentioned. For instance the presenting of the one as Abelia x grandiflora 'Kaleidoscope' but not the other as Abelia x 'Edward Goucher'.

 

So what colour do you call this red? I think it's pretty similar to what is shown here.
Thanks for the nomenclature lesson - of course I copied the name from somewhere. Though this is not that one, I may as well give the full name of that: Rhododendron 'The Honourable Jean Marie de Montague'. I keep accusing plants of being that, and it's supposed to be in the rhody garden, which is not that big- I'd love to find it.