1944 SENTA, pair with one inverted overprint

Vertical pair with one inverted overprint may occurr due to the row by row overprint process. It is known that the cliché of five-pointed stars was handmade so that the stars are cut by hand from linoleum strip. They cut out ten stars in one horizontal strip. Overprints were done row by row, all five rows until complete half-sheet of 50 was overprinted. There were two phases: first five-pointed star in red and then, on top of it, text in black color.

Inverted black overprint on upper stamp - position 10, normal black overprint on lower stamp - position 1. Both red overprints at position 1. Certificate Velićković.

Inverted black overprint on lower stamp - position 1, normal black overprint on upper stamp - position 10. Both red overprints at position 10 (from Jay T. Carrigan exhibit).

Scheme of half-sheet of 4f with one inverted black overprint row. Blue rectangles shows position of both pairs. Note that due to the vertical pairs that I have seen, inverted overprint could be at second, third or fourth row.