The problem does not seem to be what I thought it would be, I'm currently investigating, do you remember if you specifically tried to look at the "turns" graph from the game over screen or if the error happened as soon as your game ended?
This happened as soon as I flipped my final card over and the points tallied up - I never got to the stats screen.
I released another update, the problem should be fixed now. Thank you again for reporting this!
I'll have to wait for the next +Len^Len run to be 100% sure though :)