What is this? "ignoring error: RusticError"

[kapitainsky]

One of my rustic backups always prints:

[WARN] ignoring error: RusticError(ArchiverError(FromStdIo(Os { code: 60, kind: TimedOut, message: "Operation timed out" })))
[WARN] ignoring error: RusticError(ArchiverError(FromStdIo(Os { code: 60, kind: TimedOut, message: "Operation timed out" })))
[WARN] ignoring error: RusticError(ArchiverError(FromStdIo(Os { code: 60, kind: TimedOut, message: "Operation timed out" })))

Everything works, backup is made but I am curious what these ignored errors are. Any way to identify which files are responsible for them?