Once upon a time, before production, a large portion of the included entities (at the time) were CP ships. Not long (as I recall) after the switch to Darkness (might even have been at the same time) the list was completely redone with some new ships (prequel ships and a few others from newer sources) that were not, at the time, assigned as DCs.
Then the DC and CP lists were both redone, and some of those CP ships became produceable, and new CP ships were introduced. This was the start of the current system, where "retired" CP lists are rare/not available for production.
There are a few rare entities that were not on the CP list at any time, but most of the not available for production ships were CP at one point.
____________"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."
Only fools and children dream of heroes.