Hmm. I'm not sure it's as easy as moving north. Things like leaf rust disease and the coffee beetle borer aren't likely to go away anytime soon, despite the amount of money going into combating them.
In addition, altitude plays a significant role in the ability to grow coffee, and an Australian paper from this year cites a paper from 2015 projecting at worst, ...hotter weather and changes in rainfall patterns are projected to cut the area suitable for coffee in half by 2050 across different emissions scenarios. At best, places like Brazil and Mexico are going to have socioeconomic challenges facing their farmers, which play a not insignificant part of the agro-economics.