If you use the Orchestrator REST API’s to achieve this.
Get All the Queue Items
https://ORCHESTRATOR_HOSTNAME/swagger/index.html#/QueueItems/QueueItems_Get
2)Look through each Queue Item returned in the results from Step1
For each queue item use the following Rest API call
https://ORCHESTRATOR_HOSTNAME/swagger/index.html#/QueueItems/QueueItems_PutById
Set the DeferDate field to the new value
The below ticket provides some more context around the approach.