Change of status when I-94 expired and extension in progress


New Member
My L1B visa expired in Aug 2014. My I-94 expired on Jan 31 2015. My L1B extension filed on Jan 5,2015.
I already have an approved H1B petition from previous year. Now,
Can I apply for Change Of Status to either H1 or H4 when L1B extension is inprogress and Visa and I-94 expired?
If Yes, once Change Of Status is approved, do I need to leave US and go back to home country for stamping?
Can I apply ChangeOfStatus to H4 and then after few months again apply ChangeOfStatus to H1 to avoid leaving USA?