Thanks to falschung study on this issue stampworld.ca , TSF thread I can assume that these are forgeries or second reprints . I did not find any secret markings on any of these, all with poor yellow crusty gum.
Maybe @falshung Can do a quick examination to confirm if forgery or reprint ? I always appreciate learning more from your analysis .
It is a great website, very informative and exceptional data base.
The stamps pictured are all forgeries. They are on grayish paper with thick gum There is a noticeable lack of detail and no secret mark compared to the genuine on the right The "good part" is that forgeries are nowhere near as common as the reprints so they have some value as keepers. More info on the 1921 Definitive post