Hi My German stamp expert friends. I purchased a group of cancelled inflation stamps from H Baum a collector in Germany. One of these has the expertise mark from Infla on the back with the initials wa and a pencil notation that looks like 1a. This is the 2m over 200 stamps.
There are a dizzying variety of these in Michel Spezial and I am assuming (maybe wrongly) that this one may be a bit special as they went to the trouble of getting it expertised. Any help, thoughts, ideas?
On a related question - if this isn't one of the high value ones why expertise in the first place?

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