Re: 3 Registries for the Yamato?
What is so wrong with certain rare Federation starships (Enterprise and Yamato among them) possessing dual NCC registries? (one honorific/historic, the other formal)
Think of it this way: We know that Picard's Enterprise was NCC-1701-D. Maybe it was also NCC-71809, just as the Yamato could be both NCC-1305-E and NCC-71807.
"The way that you wander is the way that you choose. / The day that you tarry is the day that you lose. / Sunshine or thunder, a man will always wonder / Where the fair wind blows ..."
-- Lyrics, Jeremiah Johnson's theme.