If H1B is extended, will USCIS send a new I-94 for dependents (H4 holders) also?
--NO
Do you have to specifically apply for H4 extension or (new I-94)?
------------YES, H4 holder need to apply H4 extension with form I-539, copy of valid I-94 (front and back) copy of Primary H1 holder H1 approval notice and I-94 copy front and back, passport pages of H4 holder, Fee
Who applies for this...
-----------H4 holder has to sign the form I-539, pay the fee
is it the Employer or the application?
---------applicant, but employer/lawyer can send it in same envelope of H1 extension
What is the pocedure and how much does it cost?
------------check form I-539 from USCIS site and note the fees