I agree the above is the most likely scenario, but there was that one analyst who predicted Apple would release a 32GB RAM MBP in Q4 2017 using desktop RAM. Such a model might appeal to some customers who are willing to trade some battery life for the extra RAM.
They could call it MacBook… Pro?
I hope they do something. The 15-inch has allowed for 16 GB max RAM since the Early 2011 revision, so if they don't change it this time, it'll be seven years. That's kind of ridiculous.