The problem that we are having is for the CT-5.4. There is no way to file those online with the NY online services unless you want to create an account for every S Corp you are trying to do an extension for. Based on a phone conversation with New York Department of Taxation if you want to mail in an CT-5.4 extension with NY you need to request permission and they will mail you a blank form to fill out and send back in. With the extensions due on Friday that is no longer an option.