Retain Pivot Table Date Format After Pivot Refresh

Hello - Hoping someone can solve how to retain a pivot table date format after the pivot table is refreshed.

I would like for the pivot table dates to retain a yyyy-mm-dd format. I have attempted a few solutions but cannot seem to achieve consistency.

On the Pivot tab, columns B, C, and S appear to retain the desired format after the pivot table is refreshed, but I am not confident this will be true after all of the data is entered.

Column D demonstrates clear evidence of the inconsistency, as it continues to revert back to the mm/dd/yyyy format after the pivot is refreshed.

Thank you in advance for your assistance.