OS - not much to offer you - I expect you have seen this:
"Aeronautical Information Circulars (AIC) are notices containing information that does not qualify for the origination of a NOTAM or for inclusion in the AIP. As a general rule, AICs refer to subjects that are of an administrative rather than an operational nature. They are, however, also used to publish advanced warnings of impending operational changes and to add explanation or emphasis on matters of safety or operational significance [my italics]. Aeronautical chart issues and corrections are also notified through the medium of the AIC."
You will see from the list of Pink AICs that several important issues are covered, and our company 'passes on' a few. I do not think they have any 'legal status' as such, but it is indeed a bold pilot/company that ignores them.