My parents (US Citizens) are looking to get their Chinese L Visas.

Based on my understanding, the NYC Embassy has MA under it district and does not accept mailed in Visa Applications (I got my Chinese L visa this past year in person).
May they mail their applications to another embassy in another city (Chicago? Houston? etc) who accepts mailed in applications? Or will we have to make the trip to NYC and submit them in person? As MA residents, are we only permitted to use the NYC Embassy?
Thank you for your assistance!