Based on that, there's nothing to stop them from implementing it anyway. (Except that the whole {supposed} point was to provide guidance to the public and manufacturers.)
I'm going out on a limb and taking a guess that you are not familiar with the Federal Administrative Procedures Act. There is a lot to stop them.
Don't take my word for it, call Pres. Trump and ask him how the repeal of Obama's DACA decree is working out.