Would four Unicorn-type aviation-support ships have been numbered Unicorn 1 through 4 or individually named?
Short answerThey would have had individual names, and the cited files make it ninety-nine percent certain that the next ship would have been HMS Ocean.
NotesThe planned follow-ons would have received individual ship names rather than numerical designations. The cited files make it ninety-nine percent certain that the next Unicorn-type aviation-support ship would have been HMS Ocean. That is a strong archival judgment rather than an absolute certainty. The name belongs to the proposed four-ship support train.