As often happens in PADing / PESOing / whatever, the shot you aim for is not always the shot you get.
On my walk to work the previous day I had kept a weather eye out for potential photo ops for later in the week. One that I spotted was this sandwich bar which was brightly lit inside, making it stand out decently against the pre-sunrise greyness. (Though to be honest it would probably be even better come autumn when the outdoor light is paler and greyer still.) On that occasion there were no people outside but some inside, and I thought to capture the building, and the flag on the pole alongside it.
And that was indeed the portrait shot that I took. But once I got it into Photoshop I found that the tableau of happy breakfasters was more interesting than the building alone. They stand in contrast to the fast mover on his way to work, who has no time for such frivolity. So the portrait becomes landscape, and that's what you get.