Types of work item statuses in IEX strategies?

Hi IEX experts,

Is there a comprehensive list/guide of types of statuses for 'work items' under strategies? What I would like to understand is what conditions do some of these statuses appear?

1) For example, we have several bill-to sites (this is our operating level) with missing email address and the first work item is a dunning letter. This work item is in error and we can see it under DETAILS button as well as HISTORY --> CORRESPONDENCE for which we have an option to 'resend'. Since there is a date populated under COMPLETED, do I assume this work item is 'done' even though status is ERROR? It looks like this is the design, but just wanted to confirm.