Hi,
I just required this Bavaria stamp, 1849 Michel #4I, Scot #3 (too bad about the crease, but I knew that when buying) :

Michel (Spezial Catalog 2011) lists a plate error "4 I PF II", where the Y in Bayern has a thickened foot (lower right part).
That IS what I see on this stamp: the lower right part of the Y is broader than the middle part of the Y:

Searching pictures of other 6Kr stamps on the web, I cannot really confirm nor deny this is indeed that plate error.
Does anyone have a sample of the 'official' plate error 4 I PF II ?
Would be great !