Not convinced. Pah. Still, why take it from me when you can take it from a published anthropologist!
I am of course talking about Kate Fox, publisher of Watching the English, who, in Chapter 4 (Linguistic Class Codes) proclaims...
'Tea' for the higher classes, is taken at around four o'clock, and consists of tea and cakes or scones (which they pronounce with a short 'o').
Yes, that's right. The upper class pronounce it 'scon'. And if that doesn't make it posh, I don't know what does.