First attempt in mono tub - Golden Teacher

Cheeky loner - This is my first post ever as well as my first attempt at cultivating mushrooms. So far, everything has worked well, and after successfully colonizing my bulk bags, I now have three mono tubs in operation simultaneously. Two tubs are still in the colonization phase. The third one technically is too, but there is already a single fruiting body growing here. Now, I wonder how I should proceed. Do I let it be, or do I remove it? Does this have any impact on the remaining colonization of the tub? What do you suggest? Also today was the first day I opened the tub in order to get a proper photo of that fellow.