Can we get the closing reason for event-based-effects? Some of these questions need to be locked/closed based on such event expiration. So for example Closing Reason: Event Expired
SE sites only get three custom close reasons, and currently they are as follows for Travel-SE:
- price-shopping for specific goods or services
- constructing travel and tour itineraries
Also, I don't think there's a specific reason to close those questions -- they all carry a time stamp, so users should be aware information may not be valid any longer, due to the nature of the event. SE community obviously carries no (legal) responsibility as to whether the information is accurate, so I don't think there's much more to be done.
However, I'd argue that a post notice would be nice in such occasions, but unfortunately the available ones are not modifiable by Travel-SE mods.