8 – Webform Validation – adding validation on a date field to be not greater than another date field entered in the same submission

Drupal 8 webforms
We have a procurement completion date and build completion date. Build completion cannot be earlier than procurement completion naturally.

I tried setting this up by adding the min date validation for build completion using the token below:

This gave me an error stating the field is recursively being called and it broke the webform.

Is using webform submission values token on the form being filled possible or am I going about this wrong?