Well it sounds like an explanation is required- no evasion on my part, but your question only served to confuse. Firstly you are confusing National Archives access rights with security classifications. TNA holds a number of files that are defined as "closed " (until xxx). This is usually for diverse reasons like people and/or relatives still being alive all the way to them containing data which might be useful to certain nefarious parties. These files often won't have a security classification - they'll just be 'Open' or 'Closed'.
Your term ‘classified’ merely means that a file has a security classification: it can/could be Unclassified; Official; Secret, Top Secret etc. There is no classification called ‘Classified’ – the term just indicates that a file may fall into one of the categories above. And because ‘Unclassified’ is a classification, it can mean that a classified file has no security restriction and can be accessed.
What does confuse things is that many TNA files DO have security classifications - as was the case with G-AAGX.
So to maybe clarify things, as far as I know, there are no access restrictions on any of the Hannibal files, and the security classifications were removed many years ago (see above). From memory, the security restrictions were removed around the same time (1949) and all files have been open since the 1970s/80s.
I hope this explains things and maybe save people thinking that files at TNA are 'classified' and not accessible. TNA's search engine is very good at simply explaining whether a file is 'open' or'closed', whatever its classification is/was.
Hence, the statement, “classified or Secret” contradicts itself. It’s like asking “is it a bird or a chicken?”.