Madonna And Child Diffrence In Stamps

Hello guys here I have two stamps of madonna and child which seem to have some diffences between.

the diffences I notice are the outline of madonna's dress seems to have a light green line going around it also color below the dress and to the left of the dress are diffrent also the back ground color is diffrent and a diffrence in the heads of both madonna and child and body of child and maybe more that I havent spotted.

Does anyone have any knolege on this ?

I dont think the ground should be redish color in the stanley gibbon catalogue the images of this stamp is show white on the ground.

The green line is a shift in one of the colour plates, also known as poor colour registration. I know some collectors look at that as a variety, but personally I just think of it as a lack quality control at the printers, and not something that should be celebrated. But that's just me.

Some collectors like things like this because it makes the stamp diffrent to the rest of them.