I'm pretty sure that Old English Sheepdog's are born with a natural tail. We had one once; she was bought from a breeder (this was about 17-18years ago and we had no clue about rescue) and her tail was docked. It was what was considered standard.

I thought her docked tail was really cute because to compensate she wagged her entire bum, and there is nothing cuter than a whole bum wag! But, if I had a choice it would be natural for me.