premise: USS "Kamehameha" (SSBN-642) (called "Kamfish" by her crew), a "Benjamin Franklin"-class ballistic missile submarine, was the only ship of the United States Navy to be named for Kamehameha I, the first King of Hawaii (c. 1758–1819). She is one of only two ships of the United States to be named after a monarch. She was later reclassified as an attack submarine and redesignated SSN-642.
hypothesis: The "Kamfish" was originally classified as an attack submarine.
reason: Reason:  The "Kamfish" was REclassified as an attack submarine.  Why: Use of a nickname; key words are a very close match.