H4 to L1A COS

[jarus]

Hi,
I am in US on H1b with approved I-140. My wife is in India and L1A blanket (manager position) got recently rejected. She has SSN when she was on H1b before in 2006-07. She has a valid B1 visa. So looking at best option as she would like to be here as soon as possible. 

Option 1: Stay in India and apply for L1A Individual and wait for several months and get it approved and go for stamping and then come here. This is safest option but will take a long time.  
            Question: a). While she is India should she apply for vistors visa or H4 so that she could visit me for a few weeks and go back as she works remotely in current role.  
                            b) If she comes on H4 or Visitors does her B1 gets cancelled?

Option 2: Company applies for L1a ind and allows her to apply for Leave of absence for 6 months. She comes here on H4 permanently.  
           Questions: a) does it matter if she applies for H4 and come to US before or after her company applies for L1A petition?  
                             b) While she is here in US on H4, she applies for change of status soon after. Is it possible to file both concurrently and if so should She will have to apply for COS or her company. Or can her company apply for both right from the start. 
                             c) On concurrent filing, how does COS and L1 approval effect each other, i.e. COS becomes current when L1 get approved? does both I-797 come together? 
                             d) In my research here, I concluded that has soon as her COS is approved (i797) comes in, she can work immediately and whenever she goes out of India will have to get her Visa Stamped.  
                            e) If COS is denied and L1 is approved, will her H4 and L1 approval still be valid, then she would have to go to India or Canada/Mexico (as it is not her first stamping) to get it stamped?  
                            f) I read that once a COS is filed then you cannot go out of the country? is it true?

Option 3: When Company applies for L1a ind and allows her to apply for Leave of absence for 6 months. She comes here on H4 permanently and files for EAD.  
            Question a) When EAD card comes in sooner, can she work directly for the same position in USA. (would this depend on her company if they allow it)? 
                           b) And if they do allow it, and her L1 get approved, will she still have to apply a COS from H4-EAD to L1 and still work while it is being processed. 
                           c) Can she apply for for EAD and COS concurrently?

Thanks,
-Jarus