Castria's download settings are under Settings → Downloads. They apply to every show unless you change them for a single show.
Open Settings: on a phone, tap the menu button (☰, top right) and choose Settings. On a computer, Settings is in the bar across the top. Under Downloads:
- Download new episodes automatically: new episodes download as soon as they come out. On by default. Turn it off to download only when you tap the download button.
- Limit downloads per show: keeps only the newest few downloads of each show and deletes older ones. Off by default; when you turn it on, choose how many (3 to start).
- Delete after played: deletes an episode's download once you've finished it. Off by default.
These three work independently, so you can mix them. For example: download everything new, never delete by count, and delete what you've finished.
Apply to all shows copies these settings to every show, replacing any per-show changes.
Saved episodes, episodes in Up Next, and the episode that's playing are never deleted automatically.
To give one show different settings, see How do I change download settings for one show?