It would be cool if it was intentional: put different parts in Federation, Klingon and Romulan territory, to make it extra hard to get them all.
Seems likely. Although it's hard to say EXACTLY when he was hiding all of the information, it might not have mattered as much. If we're talking post-Hobus, it's probably not hard to move around.
But given the looks of his wardrobe, it seems like the 2370's.
Also just a side note, good on Discovery for not just arbitrarily and for no reason "visually updating" things that don't need to be visually updated.