This is my fault as, after the stained-glass was restored, I am the one who set the glass into the wood sashes and glazed them.
Oddly, I think I like them better upside-down!
WILD & CRAZY UPDATE!
Just after writing the above, I looked again at the lower sashes.
They are, indeed, reversed from what they used to be.
But, they have actually been positioned correctly for the first time in 124-years!!!!!!!!
I have to laugh at all this.
While writing the first part of the post I was punching myself in the head.
While writing the second part I was thinking: You are inadvertently brilliant!
And thanks, Meike from Germany!