Re: The Constellation's registry number
Kirk said there were only twelve like the Enterprise in the fleet, but more than twelve Constitution-class ships have been counted.
There you go, 12 starships Enterprise Class and a yet to be established amount of Constitution Class starships.
"The first duty of every Starfleet officer is to the truth, whether it's scientific truth or historical truth or personal truth! It is the guiding principle on which Starfleet is based! Jean-Luc Picard