This was Kenneth Washington's debut as Sgt. Richard Baker, the crew's new radio man. Interestingly, there was never a back story as to how he got to Stalag 13 or what happened to Kinch.
Although Sgt. James Kinchloe is never seen again (as Ivan Dixon left the show after season 5), no mention is made of him escaping, being transferred, or killed by the Germans. Between Col. Klink continuing to boast of his zero escape record, and the light-hearted nature of the show making it unlikely that a main character would've been killed, it's therefore easiest to assume that Kinch was transferred to another Stalag (where he could've potentially escaped).
There is a new arrangement of the theme at the end of the show.
This was Chet Stratton's last guest appearance in the series, He portrayed both French Underground agents and German scientists.