Congratulations! If the petition is ready for filing now, you can go ahead. Once you have moved you can update your information with USCIS.
Samuel Ouya Maina, Esq. 415.391.6612 email@example.com Law Offices of S. Ouya Maina, PC 332 Pine Street, Suite 707 San Francisco, CA 94104
You can start the process for your family from San Francisco or New York. However you need to inform USCIS of your change of address by filing AR-11 and updating the information on all applications filed.
This response is general in nature and cannot be construed as legal advice, given that not enough facts are known. Any comments offered on Avvo are of a general nature only, and are not meant to create an attorney-client relationship. If you would like additional information based on this response, please contact my office at 510 657 7665 or 415 902 0832 to schedule a consultation.