Attendee statuses are not supported for migrations from GroupWise.
When migrating from Exchange or Microsoft 365, attendee status will not be migrated for any appointments with an external organizer.
Appointment statuses will be migrated for all internal events.
For external users, attendee statuses will only be migrated if the external user sends an appointment response.
Statuses of individual appointments in recurring series are not migrated. e.g: the appointment is recurring and it's repeated every day of the week. The attendee accepts the first day, declines the second day etc. It will migrate the status of the entire sequence. e.g: user accepted all events / entire series.
External users (users, outside of migrating domain) acceptance statuses are not migrated.
If the organizer's mailbox no longer exists on the source or cannot be accessed for some reason, then CloudM Migrate cannot access the acceptance status info and therefore will not migrate them.
Exchange / Microsoft 365
When Exchange / Microsoft 365 is the source, you will see the setting 'Migrate Non-Organizer Attendee Statuses'. When enabled, CloudM Migrate will attempt to migrate attendee statuses for appointments where the migrating user is not the owner (when the owner is being migrated attendee statuses are always preserved). Due to API limitations, for any appointments from outside of the domain and from any accounts that no longer exist the attendee status will never be migrated.