I-94 expires before Visa or i797B expires

[mohai94]

Hi,
I just recently landed in US on H1B.
1. My stamp visa and/or i797B expires on Dec 2017
2. But during my PoE at Abhudhabi, i797 issues only till Jan 2017. (Just 6 months duration validity)
3. I have not changed my employer. Its the same employer who sponsered my visa....

[nonono]

I have a question:

My I-94 expires in a month, is there a possibility that i take a cruise to mexico and they would renew my i-94 for another 6 months? (I have a valid passport and visa till 2014), if not how can i renew it without going to my home country, i DONT want to file for an...

[Spri]

All,

My current I94 will be expiring on 29th Apr.
My employer has already filed the L1A conversion (Current Visa is L1B individual)

My question
1. Can I file Form I-539 which is for an extension of stay?
Purpose of doing this is - I (My employer) will...