Your lawful nonimmigrant status ends, and you are out of status, when your Form I-94 expires, even if you have timely applied to extend your nonimmigrant status. Generally, as a matter of discretion, USCIS will defer any removal proceedings until after the petition is adjudicated and USCIS decides your request for extension of nonimmigrant status. Nevertheless, DHS may bring a removal proceeding against you, even if you have an application for extension of status pending. Even though you are not actually in a lawful nonimmigrant status, you do not accrue “unlawful presence” for purposes of inadmissibility under section 212(a)(9)(B) of the Act, while your extension of status application is pending if it was filed prior to the expiration of your Form I-94.
Although you are out of status, you may be permitted, depending on your classification, to continue your previously authorized employment for a maximum period of 240 days while your extension application is pending if USCIS receives your application before your Form I-94 expires, and you have not violated the terms of your nonimmigrant status. You may be required to stop working immediately when the first of the following events occurs:
• 240 days elapses from the date your I-94 expires; or
• USCIS has made a final decision denying your extension application.
If your application for an extension of stay is approved, the approval will relate back to the date your Form I-94 expired, and your status during the pendency of your application will then be considered to have been lawful. If your application is denied, you may be required to cease employment and depart the United States immediately. In addition, any nonimmigrant visa in your passport granted in connection with your classification becomes void. Once your visa is void, you must submit any new visa application at a U.S. consulate in your home country (not a third country, except in rare instances as determined by the U.S. Department of State).
Note that the rule applies for extensions of visas such as H1B, L1, O, but not H4 EAD. For the H4 EAD extensions, please file 120 days before expiry and if expired you are technically not allowed to work until the next EAD is approved.