I am on L1-B with employer A.Employer B has filed H1-B as COS with start date as 14 March 2011 and received RFE for same for which employer is responding by this week.
MY Question.
1)is my change of status date is same as employment start date of 14 March 2011 or it would be effective the day i join employer B?

2)if my H1-B gets approved on say 7 March 2011 with start date of employment as 14 March 2011,can i continue working for employer A for 2 weeks till 21 March to serve my notice period and then join employer B and this is legally allowed by USCIS to serve notice period.

3)if not then at the time of filling RFE response can my employer B request for change of start date from 14 March to 21 March 2011 to USCIS?