Really weird, I just started an explore action on my well, just after I'd noticed I suddenly got an extra 6 population from somewhere (easy to notice as I was on zero population).

Then my population just started jumping up, from minute to minute it was going up in hundreds! I thought great, and it stopped at 1244, but then this morning, I noticed I was roughly 1200 carts short of what I had the night before.

There's nothing in the town or battle reports, basically it seems that I've converted some carts back to population, which is annoying because I'd rather have the carts at this stage.

Is this a bug or part of the game? It's really set me back as it takes ages to make those carts again.