At Oxford and Cambridge in the UK one gets their Bachellor's degrees upgraded to Master's 2-3 years after graduating provided one hasn't been arrested or divorced.
Huh, I looked it up and that's sort of the case. But I don't think they "upgrade" your degree, they just award you the rank of "Master of Arts". This would appear to be entirely different from earning a Master of Engineering/Science/etc, or even an MA at any other school, which is an actual degree.
There was a whole ceremony and I have a certificate that says Master of Arts, it looks exactly the same as my certificate that says I have the degree Bachelor of Arts.
None of this is helped by the fact that the primary requirement for your degree is to be "touched by grace" after holding one of 5 fingers while a man called a Praelector says in Latin something to the effect of, "These 5 people holding my fingers are jolly good chaps and chapettes and should be given the degree of ..."