When can/should I go to immigration to extend my one-year non-immigrant O visa? The last few times, I've gone 30 days before my visa expired. Can I go two weeks before it expires? Can I go the week before? Is there a hard-and-fast requirement to do this?
TLDR : Answer Summary
You can apply for an extension of your one-year non-immigrant O visa any time from 30 days before your visa expiration until the day it expires. Some immigration offices may allow you to apply with up to 45 days remaining on your current visa. There is no strict requirement to apply earlier than 30 days, but the latest you can apply is by the expiration date of your visa.