Hi Mindy,
WIP adjustments should NOT be done for tiimesheet transactions, only timesheet adjustment should be done. WIP adjustment on timesheets can mess up your actual cost and you will see data discrepancy across different portlets.
Now to answer your question about changing the cost type - Cost Types are dependent on the task against which the actuals are entered. So if you want to change the cost type of a timesheet transaction, the first step would be to change the cost type of the Task against which the actuals are logged against. Then adjust the timesheet. But there is a catch here - since your requirement is only to change the cost type and not the actual hours, adjusting the timesheet will not generate any new transactions. So you will have to update some value like User Value 1 or 2 and then resubmit the adjusted timesheet. Once all the jobs have caught up, the timesheet will flow into WIP with the new cost type.
To change the Charge code - Adjust the timesheet and you should have an oiption in the timesheet page itself to select the desired charge code. Select it and submit and it will populate new transactions with new charge code.
In case you want to change both charge code and Cost Type for one timesheet, then you dont need to update the User Value 1/2 because change in charge code will force the system to create new trasnsactions.
Hope this helps.
Thanks,
Jerin