Hi everyone, I'm got a bit of a puzzle on my hands. I'm researching my paternal line and I've come across a weird change in our surname. My surname is Potter as is my father's and my grandfather's. However both my father and my grandfather have the unusual middle name 'Stratton' which thankfully they didn't pass onto me

My father also seems to think that his grandfather had the surname 'Stratton'.
Which begs the question how did our surname change to Potter? My best guess is that perhaps my great grandfather died young and my grandfather was adopted by a new man and double barrelled his surname with the new father's surname becoming Stratton-Potter or pehaps shifted the Stratton into his middle name and just took 'Potter' This name then somehow became simply 'Potter' with the Stratton part shifted into the middle name (or already was that way) and then died out with myself.
Is this kind of thing usual or have any of you come across it in your research or am I going off on a wild tangent? I've managed to find someone who could well be my great great grandfather in the 1911 UK census so it'd be would be interesting to see if this kind of thing happened in the time. If not I guess I'll just have to wait for the birth certificate to arrive to definitely confirm that the person I believe to be my great great grandfather is indeed related to me.