Getting I94 extended after passport renewal

I’ve entered US (Port of entry SFO) in Feb 2014 on H1B visa and got I94 until the date of my Passport expiry in Jun 2014, while my visa will stay valid for next 2 years.
Now when I have got my passport reissued, I need to get my I 94 extended too.
I’ve learnt that there are 2 options of getting this done:
1. Cross the borders, either to Canada or Mexico, and re-enter US. New I94 will be issued.
2. Go to Customs and Border Protection (CBP department) at the Port of Entry and get it re-issued.

I would like to go in for the latter option but have no clue of the procedure of getting this done. 
Can it be done online or by appointment at site only, what kind of form filling would be required, will this be a paid service, how much time does it take for getting the I94 re-issued?

Not sure if CBP does this. This is because CBP is external facing, meaning it faces foreign arrivals and officials cannot be approached after you have arrived. However I may be wrong. Do look up I-94 rules on www.cbp.gov and also form I-539 on the uscis.gov website.

Best wishes

Dr. Sandeep Shankar, Colorado heights University, Denver, CO 80223, USA. www.chu.edu; sshankar@chu.edu