I just had an interesting thought... we ordered 2x 10 boards and not 20 boards, i.e. there were two separate orders of identical 10 boards done at different times. It was cheaper that way.
Anyway, it would be interesting to compare the boards from two different batches... Unfortunately you have one batch Brendan while I have the other
I was planing adding a few more for you but in a rush left them on my desk. Compare photos?