Failback is identical to failover in every way. No temporary objects are created and no cleanup is normally required. The main thing to note is that if an undo pod for the current source pod is identified by the SRA, it will not be able to demote the source pod and the recovery will fail. To enable a recovery, manually eradicate any undo pod listed under the source pod and retry.
An undo pod can exist for the source pod if there are quick recovery operations back and forth (in less time than the eradication window which defaults to 24 hours). If it is not possible to eradicate the undo pod (for example if safemode is enabled), a disaster recovery operation must be run for the recovery and then re-run the recovery when the pod is eventually eradicated by the timer.