Restrict date update if 14 days after currently selected date

I feel you are very new to Quick Base you may want to make a copy of your app to first do this on a test copy of the app.

1. Edit the field properties of the. Field called [Old Actual Est Date (concept)] and change it to be type of formula numeric

2. Make the formula box entry be [Actual Est Date (concept)]

3. Edit the field properties of the field [Old Actual Est Date (concept)] to be of type numeric.

Now your existing form rule should work for all your records.