I see the Star-sticks made the Charlton guide!
Interesting
I do not have the catalogue yet but are you able to share the jist of the catalogues content?
There is precedence in the catalogue (like the hidden plate numbers) to cover items that may be a result of print registration issues.
Through this whole process I have developed an interest in subtle changes that are created in notes due to some very small changes in the print registration. Hopefully I will compile and share it at some stage.
But I hope that eager sellers do not abuse the information about the star sticks..
So far if you had a note in the the following HP- prefixes with a clear star then I would consider that you have something that is not common:
HPA
HPV
HPZ
The same would apply to any non HP- prefixes (although the sample size for 2011 HA- prefixes precludes any definitive conclusion)
In all other prefixes one can find star sticks although some are more frequent than others (e.g. HPY, HPW less frequent, HPD more frequent) So much so that in some prefixes finding a non-star stick is an aberration.
I have not had much time lately but will get to compiling this information in a more organized manner especially if there is more interest after the Charlton inclusion.