Thank you... that is helpful. Would something like this be allowed:
1. we publish a single cache, on the day before the event, it will be permanent.
2. On the event day, the contents of that published cache container will give clues and coords for a few other caches on-site. When particpants solve all caches or puzzle then they get some sort of token or something.
3. After the event, we change the contents of the cache contatiner to be more generic and leave it in place as just a single stand-alone cache for the long term.
If something like that might be allowed, then the follow up question is: Could I, as the cache owner revise the on-line description from time to time? for example to mention the open house initially, and then to remove such references later?
Heidi