How exactly are you going to have a new FC soon? If you discovered a method to change it, I'd love to hear it. Hate the fact that my FC starts with "0920" (Hate zeros as the first or last number of the initial part of the FC)
Ah, yes, portrait mode, surely the best way to film a row of people. If only there were some way to fit a wider shot, at the expense of height... if only...
Anyways, you can do change the FC without formatting with GodMode9.
In CTRNAND > data > sysdata > 000010032 > erase 000000000