When is the right time to contact my choice of the B3? Multiple Degrees?

[Yanji]

Another tid-bit of information to know is that once you have earned a bachelor's degree you fall into the category of being a post-bac student everywhere.

Regardless of your student standing, very few universities will give a 90 credit block transfer for a second degree student. Most places will just accept credits on a course-by-course basis and perhaps waive gen eds.

I would skip the Social Science degree and go for a BSBA. You said that the BSBA was for your career, so why not get an MA in whatever Social Science discipline(s) interests you after the BSBA? Interdisciplinary MAs are more numerous, generally cheaper and less contingent on your personal/career situation than MBA programs. Not to mention that if it's just for personal reasons, you have a lot more choice in terms of individual program/institution and mode of study, whereas MBA programs require more careful selection. There are very few online (max 4-5 in the US) or part-time MBAs which would be able to even remotely reliably facilitate career-switching, and even then it is almost universally discouraged by business schools and recruiters.