I fully understand wanting to talk to someone live. But that probably isn't possible.  You can file any party after the 15th as long as you didn't apply for an extension that hadn't been accepted as of yet.   Once it's accepted you will be able to file them.  If no extension was done it should work the same on the 16th or later as it did before the 15th.   I do know that after a certain date, which right now I am not sure exactly what it is but like example: 10/16, it states you must wait until the next year to efile any returns for the year your in.  If that happens to you.. then print the returns with the federal form #8948 and do a mail in.  Hope this helps.