The appearance of Captain James T. Kirk's (William Shatner) USS Enterprise-A in Star Trek: Picard season 3 was a sly foreshadowing of the USS Enterprise-G as the hero ship of Picard's proposed spinoff, Star Trek: Legacy. Picard season 3 was set on the USS Titan-A commanded by the late Captain Liam Shaw (Todd Stashwick). The Titan was a Constitution III (or Neo Constitution) Class starship that was eventually commanded by Shaw's First Officer, Commander Seven of Nine (Jeri Ryan) at the end of Picard season 3.
The USS Enterprise-A debuted at the end of Star Trek IV: The Voyage Home as a replacement for the original Starship Enterprise, which was destroyed. The Enterprise-A was a reward for Captain Kirk (formerly Admiral Kirk), who saved Earth from destruction in Star Trek IV: The Voyage Home. Kirk commanded the Enterprise-A in Star Trek V: The Final Frontier, when the starship was hijacked by Sybok (Lawrence Luckinbill), the mad brother of Spock (Leonard Nimoy), in his quest to find God and the fabled world of Sha Ka Ree. The Enterprise-A was decommissioned after Kirk and his crew helped enable peace between the Klingons and the United Federation of Planets in Star Trek VI: The Undiscovered Country.