So, lines of code don’t always represent how long a chapter / episode will be. My entire chapters are about 42,000-50,000 lines of code… but they usually have a 20-25 minute play through. I think your best bet at determining whether your chapter is long enough or not is to preview the chapter with a timer running and read the chapter as if it were your first time reading it. Without advanced directing, complex branching, mini-games, etc. a good base line would be to have 2000 lines of code. However, when adding branching, mini-games, advanced directing of characters and overlays, you’ll need to look past lines of code.
Also, side note: I’d stay away from chapters that are less than 10 minutes long. Many people I’ve spoken to find that chapters that are shorter than 10 minutes feel like a waste of a pass… But also don’t go overboard and create 40 minute chapters lol