I filed a 7004 for an s corp which was started on april 1, 2012(short year). it was electronically filed and accepted. since i have a new software i noticed that line 5b should have been checked for short year and initial return box checked, but my software left it blank and did not check that box. should i go ahead and mail on in with box 5b checked? is irs okay with the original one? has anybody had any experience with that regards?