The H4 does not need to extend status, and probably cannot extend status if the status is not going to expire within 6 months.
The above is intended only as general information, and does not constitute legal advice. You must speak with an attorney to discuss your individual case.
Your right to work and L2 status is dependant on oyur spouse having L1 status. If his status terminates so does yours and you should concurrently file for a B visa with your spouse
It is not clear what you are asking. Visas in the US start with a letter, not a number.
J Charles Ferrari Eng & Nishimura 213.622.2255 The statement above is general in nature and does not constitute legal advice, as not all the facts are known. You should retain an attorney to review all the facts specific to your case in order to receive advise specific to your case. The statement above does not create an attorney/client relationship. Answers on Avvo can only be general ones, as specific answers would require knowledge of all the facts. As such, they may or may not apply to the question.