What happens when 3rd Party Siebel Communications Driver calls IndicateNewWorkItem() with same old a

Hi,

Please consider this scenario:

1. Driver indicated new work item with tracking id 12345 using IndicateNewWorkItem(...)
2. Driver started work item using WorkItemStarted and tracking id 12345
3. Driver updated work item using UpdateObjectInformation(...)
4. Driver started another work item with tracking id 12345 and old tracking id 12345 via WorkItemStarted(...) method
5. Driver released work item using WorkItemReleased(...) with tracking id 12345

My question is what happened to previous work item after step # 4. Will the first work item duration be from  step 1 to step 4 or from step 1 to step 5?

What happens under the hood when driver starts another work item with same tracking id and old tracking id. Is old work item with this tracking id released before starting new one or what?