In Pro 5.1.5 ajax was broken for Gravity forms in the V2 form element. As such all my sites are using the Classic Gravity Forms element.
When upgrading from Pro 5.1.5 to Pro 6.0.3 the Classic Gravity Forms element loses the link to the form.
The end result is that all pages where there used to be a Gravity Contact form no long contains the form. I then have to go to each page in the site and reconnect the form to the element.