I can confirm that one if I understand properly.
My UI is doing the same thing on my Paladin. If I log into the game as Holy, the tag on my unit frame that says Holy shows correctly. If I swap to Protection spec, and look at my own unit frame again, It still states that I'm Holy, it does not seem to update to Protection. Once I perform a reload, the tag updates correctly to show Protection on my unit frame.
I've only seen this when I've been solo. It's also the only time I've paid attention to it
So it's just a minor visual bug that does not impair any usability.