King Daniel Into Darkness wrote:
The "Captain Shelby"/licensing issue was to do with Peter David's Star Trek: New Frontier novel series. Basically, Pocket Books were assured by The Powers That Be that Shelby wasn't going to be seen or mentioned again in TV/film Trek, so they were free to do whatever they wanted with the character in the concurrent book series (which features her heavily, and I recommend if you're a fan of the character)
After TPTB "forgot" about their agreement and Captain Shelby was mentioned in DS9, one of the books had to include a bit where it was explained that the newly-promoted Captain Shelby was another Starfleet officer named Shelby, not "our" one (who at the time was first officer of the Excalibur)
Wow, that's annoying, they definitely should have used the character again, novels be damned.