Its almost a trivial process - starts on timesheet update, when set status to submitted, then the process just sets status to approved. Done.
You can control who gets their timesheets "auto-approved" by giving out the process-run right selectively (or to everyone if you like).
Dave wrote:"Delete Process Instance" - yes thats the one; but you DON'T have to give it a parameter, then it will just clear down any completed processes (good system housekeeping generally).
( If you go to the Process / Initiated link in the admin tool you can see all the "completed" stuff that the job will clear down )
Not sure about why you have odd behaviour in the notifications - I don't use that much myself to give any sensible advice!
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