posted
I dispute the definition for CA on that list! CA simply refers to a standard (heavy) cruiser with guns normal for a cruiser.
I believe the first battleships were indeed abbreviated as 'B', but then later changed to BB (possibly when the dreadnought battleships came out?). Cruisers were also abbreviated as C in the old days until armored cruisers came out, hence the 'A'. Armored cruisers are what we think of as regular cruisers now.