Digital Signature able to be signed without required fields completed

I have an existing form that was created in Designer (Experience Manager-Forms) that has multiple required fields and then has a digital signature box at the end of the form.  Up until recently, the form has always worked great and would not let the user complete the digital signature until all of the required fields were completed.  Is anyone aware of a rencent change in Adobe Reader/Pro that would allow this to happen?  My form will not let you use the "submit by email" button unless all required fields are completed, but will allow for digital signatures without the required fields all being filled out.

Thanks.

Caleb