After I finished this dough I let it rest in the fridge for about 1 to 2 hours. When I pulled it out I split the dough in half and added my first layer of butter. I then put the dough onto a tray and set it back into the fridge. I repeated the above step two more times. This lead to the biscuits having layers and them being more moist.
This made a lot of batter. It was a very lumpy batter too. If I make again I won't melt the butter for the crumble - it was more of a dough than a streusel, I had to add another tablespoon of flour to the mixture.