We filed a partnership 1065 return before the due date of March 15, therefore we didn't file an extension.  Now we need to make a change, but when we try to do a superseded return, the Lacerte program has a critical diagnostic warning: "e-file:  Superseded returns can only be filed up until the due date or extended due date, if extended.  Please uncheck the "File superseded return" checkbox in the Electronic Filing input screen.  (ref #57592)".  

Because we didn't file the extension (since we were filing before March 15), can we not file a superseded return and have to file an amended return?