L1 visa to L2

Present Situation
Myself – L2 (with EAD)
Husband – L1 (valid till 2016-March)
Kid – L2

My company has started by L1 processing

Assuming my Husband contract with the present employer at USA is not getting extended, we were thinking that he would move to L2 (if my L1 is approved). Could you pls suggest which is the best way we could proceed.

As per our understanding we have thought these could be the different scenarios L1 to L2 can be done

• Along with my visa interview
Does L1 becomes void once L2 is stamped ?
If L2 is approved can he enter to USA with L1 and then change the status to L2 later ?

• After L1 is approved, Apply COS (Change of Status) staying in USA.
Can EAD be applied along with COS ?
Once the COS is approved is there a possibility, that COS can be done on requested date. Does applicant get a chance to select the date for COS ?
Is there a possibility that COS and EAD gets approved on the same date and then continue to work in the present position using L2(EAD). Does he have to undergo new joining formalities ?

• After L1 is approved apply for L2 outside USA

Note: My Husband requires to give 1 month notice for quitting the job

Which is the best option and if any other options also let me know