Behaviour nuance: --time-only-dedupe is not truly “time-only” One subtle but important detail from further testing: With --time-only-dedupe , matching is not purely start/end It still requires locations to be “close enough” (via close_enough_loc() ) This leads to a useful behaviour: Minor location noise (formatting, duplication, etc.) → same topic updated Real location changes (e.g. C05 → C04) → new topic created Practical effect This means: Room changes surface in Latest (new topic → visible to users) Feed noise stays invisible (quiet updates or no-op) So the system ends up acting as a signal vs noise filter: Times define identity Location changes are treated as meaningful Description churn is ignored