Episode is being wrongly renamed

Episodes of the currently-airing season of Casualty https://www.imdb.com/title/tt0096555/episodes/?season=40 are captioned in the opening titles with a "story" name; there are multiple episodes or parts with the same story name. Although an episode/part number is not displayed on-screen, the convention in IMDB is to append this to the story name - for example Lethal Legacy: Episode 5. Listings sites such as Radio Times use a similar format. All the episodes in this season (and maybe a few previous seasons) are in this form.When I created the latest episode I mistakenly called it "Lethal Legacy: Episode Five" (Five as a word) and then renamed this in 260521-103515-588000. This has resulted in an episode title of "Lethal Legacy" with no episode number. I've renamed it again in 260522-104458-517000 with an explanation as I've given above - conforming to an existing convention.I'm raising the issue here as well in case the automatic process needs any manual intervention.If it is decided that "Episode" is the wrong word to use in all these titles and that "Part" is better, then there are a LOT of titles which will need to be renamed, so I'll need some help from an admin if there is a quicker way than laboriously renaming every individual episode title.