@gulaum The only processing statuses that are available in Insights are the final statuses you listed: Successful, Failed, and Abandoned
Below is the data model for Queues in Insights. On the row for Processing Status the same status are stated. Postpone isn’t included in the data model but defer date is. Since the transactions need to be in a final status, the Defer Date may get you the data you are looking for be as a point to report from, not as a way to see what transactions are in a “postponed status”. Best of luck!