Hi James,
I created an improvement ticket with our Engineering team for this. Right now there isn't a way to change the simulate log so it will overwrite the validate log (as you've experienced). If you want to check on this improvement at a later date, please refer to WIN-37216 when asking support or someone at Winshuttle.
Thanks,
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Maria Simpson | Solutions Engineer
Winshuttle North America | 4255276647
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