Over Strike? 1780 Kremnitz Maria Theresa Thaler

I have had this coin in my collection for over a year. Its not an overly important coin, for me, so I hadn't really looked at it closely. I have been writing an article and I photographed this coin for the article. While focusing I saw some thing I had never seen before( remember I don't know much about this particular strike) It looks like the first two letters of the mint signature have been struck over some other letter. I am unfamiliar with this sort of error...it looks to me as if the SK has been struck over an upside down "P" and upside down "K". Is that known for this coin? The letter puches for coins like this were hand engraved so it is possible that it is just poor(but I couldn't do half a good a job as that engraver has) engraving? {Sorry about the closeup of the letters I didn't reset the aperture on the lens so there is some colour breakdown as the picture is close to the diffraction limit} The picture of the whole coin was taken with Axial lighting hence the darker colour