Yeah, a year and you should be good unless you had some nonstandard terms in your deal. Read the deed of trust (or mortgage if you're not in a deed of trust state).
Standard terms from the uniform instrument (Form 3005 Deed of Trust for those of us in California) are occupancy within 60 days continuing for at least one year. Standard second home rider also requires one year. Here's the text from the uniform instrument including the"extenuating circumstances" language.
3005 Deed of Trust
6. Occupancy. Borrower shall occupy, establish, and use the Property as Borrower?s principal residence within 60 days after the execution of this Security Instrument and shall continue to occupy the Property as Borrower?s principal residence for at least one year after the date of occupancy, unless Lender otherwise agrees in writing, which consent shall not be unreasonably withheld, or unless extenuating circumstances exist which are beyond Borrower?s control.
Second Home Rider
6. Occupancy. Borrower will occupy and use the Property as Borrower?s second home. Borrower will maintain exclusive control over the occupancy of the Property, including short-term rentals, and will not subject the Property to any timesharing or other shared ownership arrangement or to any rental pool or agreement that requires Borrower either to rent the Property or give a management firm or any other person or entity any control over the occupancy or use of the Property. Borrower will keep the Property available primarily as a residence for Borrower?s personal use and enjoyment for at least one year after the date of this Second Home Rider, unless Lender otherwise agrees in writing, which consent shall not be unreasonably withheld, or unless extenuating circumstances exist which are beyond Borrower?s control.