I will have interview to 宣誓入籍 the end of this month. My parents are in US now, they have B2, and visa will be expired 5 days after my宣誓入籍.
Q1. -Do I have to apply extension for their B2?-No.
Q2. -Will they still be legal when they wait green card in US and B2 will expire by that time? What will happen if green card application is denied? They have to leave US as soon as possible?-You worry too much. It does not matter to their green card application whether or not they illegally stay.
If I failed宣誓入籍or I couldn’t get my citizenship paper that day at interview?
-Why do you think you might fail in the US citizenship application? Do you have any reason to worry about this issue such as criminal or immoral record, etc.? If no, you should have no problem.
Or have to wait few months to get citizenship paper.-You will get it immediately after you take the oath.
Q.3 –Can they stay in US and wait to file their green card applications? Will that affect their green card application?
Q4 – B2 and legal status of waiting green card can exist at the same time? As I understand after filing green card application, B2 status does not work automatically. Is that right?
Q 5. If I pass the interview, how soon I can mail out the application? the next day?-
Yes.