JetFormBuilder – Schedule Forms Addon
A supplementary plugin that lets you set the form availability time frame.
Scheduled form display
Set up the form to be shown or hidden on a certain day, within a specified time span, and even at a given time.
Shortcodes in custom messages
You can add shortcodes to Text and Textarea field types like pending/expired messages.
Style up the Restricted and Pending messages – the text settings are the same for both.
Prevent Default on form submission
Keep in mind that the date checkup occurs not just during the form rendering but also when it’s being submitted.