Philatelic puzzle answer

I almost forgot to post a followup to this item from last week. In July 1956 what was then East Germany created a stamp (on the left above) to commemorate the death of Robert Schumann. About 3 months later a replacement was issued. CGHill was correct in surmising that the reason for the reissue is that the first stamp featured an incorrect musical score - one written by Franz Schubert. Enough stamps were printed of each variety that they currently are considered philatelic oddities rather than rarities.