The WBC revealed it in their convention, they also said that the winner of Porter vs Granados will face Thurman later in 2018.
Keith "two time" Thurman? Well I'll be damned. Assuming the January fight is a tune up it's a let down that we won't see him take on Spence or Crawford for another twelve months at least.
I'm surprised the incompetent WBC can actually organise a convention. Probably about half a dozen people there - Sulaiman and a few folk with brown bags for Sulaiman (including DLH of course).