Bleach want "discolor" it, but it might 'de-color' it, ie. remove some of the print.

It's not really a function of 'bleach' per se, but rather of how high the chlorine + CYA is, AND whether you have a chlorine bleaching resistant print or not.

There's no way to know whether you do -- Plastimayd seems to have mostly resistant liners but NONE of the liner makers will tell you who printed the sheet, or who made the vinyl sheeting, and without that info, you can't tell.