How to do leap frog to avoid L1 to H1 Change of status?

[devex]

I am currently on L1B Visa with Company A. Company B applied for my H1B in mid October 2011 which i don't know was with a Change of Status request or not. I haven't got the H1B approval yet, its still in process with USCIS and I assume it was with a Change of Status request but i don't know what is my Change of Status Start Date. I want to continue working on L1 with Company A upto 2012 year end because of some personal reasons. I want to do "Leap frog" in order to maintain my status on L1B but as i don't know what is my Change of Status start date or may be the change of status is prior to the H1B approval date (which i haven't got yet as i mentioned above), I have following questions in this regard:
1. How can i do leap frog when i don't know what is my change of status start date?
2. How can i do leap frog if my Change of status start date is prior to my H1B approval date, which i haven't got yet as the case is still in process with USCIS?

Thanks in Advance!