Hello!

Like what Danzo said above, the Everlasting Event isn't a regular event included in the regular cycle of events. The event itself requires someone from your Group to be at least 3 months of inactivity, hence the reason for not being able to release it monthly. Most probably, it will take 3 months or more before the event comes back again in a cycle but that's just purely my guess so don't take my word for it. Thank you.