In DS9, the NX-74205 Defiant was destroyed and Sisko was given the San Paolo in "The Dogs of War" and given a special dispensation to rename (and change the registry) of the ship to the Defiant.
SISKO: Special dispensation from the Chief of Starfleet Operations to change the name from Sao Paulo to Defiant.
And there is the TOS Enterprise's upgrade from her TOS-look to the TMP-look. She kept her registry and name. Now going from NCC-1701 to NCC-1701-A might be explained as a change in classes as the 1701 was described as "Enterprise Class" in the simulator label in TWOK and in TUC could have been a "Constitution Class". Note: I consider TOS as it's own separate continuity and the TOS Movies as "bridge" continuity that could work in TOS or TNG.
In anycase, the NCC-1017 Constellation could have been an older class but still of a starship configuration. Whether she was an upgrade that kept her registry or a replacement ship or the original we don't have enough information to determine either way, IMHO.