After editing my contract today, I went back into an older submission and noticed that the new info was inserted into the old contract.

Why am I unable to update the info in my contract without it affecting old, already signed and submitted contracts? This could present many legal problems for me in the future, as I was not aware this was happening. When I click on an old submission it shows my newly revised contract and not the original details which the client agreed to when they signed their contract. Why is this happening and is there anyway to prevent it?

When you edit a submission, from the Submissions view page, a new set of data is triggered, this means you update the data on that particular entry. When you delete or update information in the email body, such as the contract terms, the old information is gone.To prevent this, you should make a new form, so, old submissions will not get affected.

Another suggestion would be to download your old submissions before applying a new change to the form and email settings.