Thanks for your answer I was confused with something that I have read regarding the APM module which states:
Attention: Sync-Only groups must be configured before you pair Active-Standby devices. To add an Active-Standby device pair to a Sync-Only device group, first you must reset the trust between the devices. Next, you must remove the devices from the Sync-Failover device group. Next, you must add both devices to a Sync-Only device group. Finally, add the devices as an Active-Standby pair to the Sync-Failover group.