When using ABC plates for dry embossing and metal dies, it is suggested to alternate the surface of the cutting plate, Plate B, the thinnest plate, to prevent warping or breaking. However, over time plates A and C can also warp but because they are thicker, it often goes unnoticed until there is a problem. To prevent this, the way I remember to flip them is to have all plates facing the same direction when in use. So if I’m using Plate B upside down then I make sure to use the other plates upside down as well and visa versa. That way, I know Plates A & C are getting the pressure applied evenly throughout their use and warping is prevented.
Sproatmeyer 