Securing a post edit form

Hi there, thank you for this incredibly useful Gravityforms Add On.

In my setup I have two forms. My first form is publicly accessible and creates a user and a post after a successful PayPal transaction. My second form enables a logged in user to update their submitted post.

Is it possible to prevent logged in users creating NEW posts via my post update form?

Would adding some sort of nonce verification help in this instance?

Any suggestions would be very much appreciated.

Cheers again for this fantastic plugin.

Thank you

https://www.ads-software.com/plugins/gravity-forms-post-updates/