Hi,
If you have to delete the whole data and reload the new data again..Then in your process chain just add the two steps:
Delete the data from PSA and Delete the contents of target.
So everytime new data will be loaded and the old data will be deleted.
Why do you require the Start routine for this purpose if you have to delete the whole data altogether ?
I hope this is what you are trying to convey.
Regards,
AL