This record (task & parent WO) in a status of APPR means these were probably set manually in some way. ACTSTART can be set when going to INPRG (which could then go back to APPR), but ACTFINISH by default is only set when going to a COMP status which can't then go back to a previous status (can only go to CLOSE).
Once you change the status to COMP it'll evaluate some of the dates and update them based on a variety of settings. For example, on the main WO, system property mxe.app.workorder.includeTaskLabTrans determines whether or not task labor transactions should be evaluated in calculating start/finish date on the main WO. By default this is off, so only labor transactions against that WO are evaluated. There's quite a bit that goes into the calculation, but I'd try in a NPE some of your examples and see what happens when you got COMP status and see if the dates make sense to you.
For performance purposes, this complicated logic isn't evaluated all the time which means that dates might not make sense while you're working with the record if users are setting it manually.
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Steven Shull
Director of Development
Projetech Inc
Cincinnati OH
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