Purple Rhododendron - Bumble Bee?

Purple Rhododendron
I have a dark purple rhododendron growing in the middle of Middle Garden. The purple flowers are a lovely colour combination with the late-spring greens, especially on an overcast day.
I found a label!
It's very possible that this is the variety Bumble Bee. I recently found a Bumble Bee label in an old box of printed photographs. My 2007 gardening journal records me buying one. But rhododendrons have been shifted around a bit in my garden, and so matching the label to the correct shrub is a bit of a guess.
The Bumble Bee rhododendrons in Google Images have varied tinges of magenta, or not, depending on the light and the camera. Mid to late season flowering? A black flare in the petals? What do you think?
Why Bumble Bee?
Further research : 1.5 to 2.5 metres, mid to late season, compact, pointy green leaves. That doesn't really help me much. Another thought : why would a purple rhododendron be called Bumble Bee? Because bumble bees are rhododendron pollinators? Hmm...