Mexico has been upgrading refineries AND has been trying for a decade to build more. I don't understand the confusion. Before the energy reform, Mexico pretty much had to foot the bill and even has the property ready for a refinery. Now with energy reform Mexico would like investors to build a refinery ( or 2). Although companies are interested in building a refinery as of yet no one has actually done anything but talk.
Just like the pipelines you saw, that is part of the energy reform and investor built. Gulf Oil can't just start bringing tankers of fuel in without investments of infrastructure. This takes years to put the pieces in place.
These articles come up all the time in Mexico newspapers, you just have to read everyday and wait for the next one.