This all depends on what kind of media they use to blast the surface. Some heavy grit media will leave enough tooth for the epoxy to stick. If it leaves a smooth surface you will need to degrease it very well, sand and then apply the epoxy.
Check with your paint supplier on epoxy coatings. Some are NON SANDING and sand or scuff like bubble gum no matter how long it has been cured. Some newer epoxies sand like filler primer.
Your 1.4 will be fine for most products you intend on using.