Can you use the time value for the hidden field in future submits?

[Casmo]

When I copy an (encrypted) value from the your_submission_date and use that value the next day, my form is still submitted. It seems I can always use it in future submits because the code only checks if the date is not in the future. See here.

Would it not been an idea to allow only X minutes ago as valid timestamp?

[parallels999]

Hi, feel free to do a PR to fix it, thanks