CMOT

Thanks for that. It does help. The risk of recurrences was one of the factors in deciding to leave it alone for now 👍

Ended up taking the car in for the warranty person to see. He concluded not a bodywork corrosion warranty issue as not internal to external type of corrosion through a panel (which is all that the corrosion warranty covers apparently) but probably very slight moisture ingress at some point relating to the edge by the seam sealant. Nothing visible though as a defect in the sealant or otherwise in the paint and he confirmed no sign of any previous paint repairs. Skoda apparently don't entertain goodwill payments unless the issue is visible from a metre away with the doors shut whereas VW and Audi possibly would. In real life the issue doesn't look too bad and is more obvious in the photo. The ultimate advice was it's not likely to change much any time soon given how long it has taken to appear. The nature and extent of a full repair would be the same even if it expanded significantly so unless it does progress I'm going to live with it and see how it goes. If it does get significantly worse I might try another dealer before getting a repair, although I think this person was being honest in his explanation, but there is too much going on in life at the moment for me to pursue it further now. Annoying but there we are.

Thanks for the replies. I've just spoken to the warranty person at the local Skoda dealership and sent him the pics. Will update when I hear back.

So today I was washing my 2020 Superb and noticed irregular lines on the inner surface of the passenger door in the paint. There is no sign of damage near the marks. I am pretty sure the car has not had any paint work done. The door edge and outside of the door are pristine. I am worried in case this is rust starting but would like to think it is just an insignificant cosmetic flaw I somehow haven't noticed before. I f it is corrosion then the paint warranty is expired and there is no perforation (yet) to claim on the bodywork warranty. Any thoughts as to what is going on? Thanks