Early Filing.
An applicant filing under the general naturalization provision (section 316(a) of the Immigration and
Nationality Act (INA)) may file his or her application up to 90 days before he or she would first meet the required 5-year
period of continuous residence as a Lawful Permanent Resident (LPR). An applicant filing as the spouse of a U.S. citizen
under section 319(a) of the INA may file up to 90 days before meeting the required 3-year period of continuous residence
as an LPR. Although an applicant may file early according to the 90-day early filing provision, the applicant is not
eligible for naturalization until he or she has reached the required 3- or 5-year period of continuous residence as an LPR.
Applicants filing up to 90 days before meeting the continuous residence requirement must still meet all other requirements
for naturalization at the time of filing the Form N-400. For example, an applicant filing under section 319(a) of the INA
must meet all other requirements as the spouse of a U.S. citizen at the time of filing

N-400 вопрос 9 - если гражданств больше чем одно надо указать страну которая выдала вам паспорт последней