If someone wants to change there submission, what is the best process?

Do they just re-register and if that is the case, is there a quick way to delete their previous responses (mass delete) or does this need to be individually done?

Is there an option that allows them to overide their previ

Your message came out just partially so please contact us with the rest of your inquiry so we can assist you.

To allow users to edit their submissions you can insert an "edit link" in the auto-responder email:

You can see more details about the auto-responders in our article.

But if you wish to change a user's submission you can also do it in your account. 

Go to My forms (1), select your form (2), select view submissions (3):

Click edit, edit the submission:

And in the end click submit:

Let us know if we can be of more assistance.