She's only in 11 episodes? Thats weird. I figured since she was the new commander, and has a prominent place on the DVD case, that she'd be a big part of the main cast. Still, if episode one was any indication, I'm not complaining about the fact she's only in 11 episodes.
She too was a last minute change. Ivanova was supposed to be in S5, but, the Actress and/or her agent played around with Salary Negotiations too long, and she didn't answer by the dedline, so, Captain Lochley was created and Ivanova was given her own ship offscreen (Though Ivanova returns in the Series Finale, which was filmed prior to S5, when it looked like there was going to be no Season 5, and it was originally going to air as 4.22 instead of Descontruction of Falling Stars).
I'm not sure why Lochley is in only half the episodes, if it was availability or her character just not organically fitting into all the scripts). Sinc she is in half of the Episodes as a regular, she is credited for all the episodes, SAG rules.