Hi Horace - We dug in, and the reason for this is that EventSources are unique in nature.
Since they auto clear based on time, or based on acknowledgement (coming in v.83), we have not historically sent out clear alerts. It's not as though the event "un-happened", it's more that it has served its usefulness as an alert. I understand that makes things tricky when it comes to integrations. We've seen some people handle this on the integration side. Another option is to have an alert rule specific for EventSource alerts that closes an incident as part of the Acknowledge payload.
There are some other options we can explore, but we'd love to hear more about what would work best for you.
