Signature Fields: Reset a Field if Signature is Cleared

I am using Acrobat Pro and have setup my form to display hidden fields once a
form has been digitally signed. Does anyone know how to go about
"resetting" this action if a signer changes their mind and clears
their signature?

Once a document is signed, I have some routing buttons that become visible to
the user. This works fine. However, if a signature field is cleared, for
whatever reason, ... the fields that were unhidden (due to the form having been
signed already) do not default to the original hidden state. I've tried
reversing the code I used to unlock the fields in the event the value of the
signature field becomes null, but can't seem to get it to work. Any thoughts?