If you want let people know about it in advance, you can add an event to the in-app bulletin. There are few benefits of doing this:
- People can add the event to their calendar (a soft "RSVP") to be sure they remember it.
- Adding an event to the bulletin generally results in a bigger audience since people can plan.
- Planning an event in advance generally also gives you time to find co-hosts, guest speakers, experts, and to set the format for the conversation which helps with moderation.