IRS said I bungled the Dual Status Alien method of filing for 2014. (I can't be an expert at it, since one can only file that way once in a lifetime right?)=====> I do not blame you; even many many tax professionals do not do it well either.
Advice from financial advisors I was given is that I have to file the two forms:
1. 1040-NR, MFS, foreign income of alien spouse reported here
2. 1040A, MFJ, all other (USA) income reported on this one=====>>instead of 1040A you may file the comprehensive form 1040; You have a dual-status tax year when you have been both a resident alien and a nonresident alien in the same year. So, in your case, should you choose to make the first year choice, you are considered a Non Resident Alien for the initial part of the year and a Resident Alien for the latter part. You will have dual status.
But these can't be filed now, right, since I already filed them before. How do I now file a 1040X and get the info from these forms reported on to that form?
=======>>As you’ve filed your original 1040A, I guess, you never start over and file another completed return of 1040A; You only need to file your completed tax return with all the schedules and attachments once. After that, you should use Form 1040X to change only the INCORRECT information.For incorrect information entered on forms or schedules, such as SCh A or etc, you need to attach the corrected forms or schedules to Form 1040X.you Do not need to attach copies of any forms or schedules that do not change
Basically, you can not electronically file your dual-status return or 1040X; you may use tax return software to file your 1040x(not all tax return software supports dual status returns)but you still need to send it by mail.