This particular overprint is one of my favourites in terms of design. It was applied to the illustrated issue in 1922 following a currency reform but a very similar one was used on an earlier issue in 1920. Unfortunately, I have no examples of that to share.
There is a question attached to this. I now have a cancelled copy of each value. It is dated 1927, five years after the stamp issue, with what is pretty obviously a CTO of some sort. I suspect that it is a commemorative cancel but I cannot identify it or link it to an exhibition of some sort. Any suggestions would be appreciated.