Transfer cap exempt to cap subject h1b

[nupuraggarwal]

I currently work for a university on a cap-exempt H1-b, I received a

job offer from a private company (which is a cap-subject employer). I

am looking to see when will be the earliest that I can start working for the

private company.

I know that my new employer will need to file a new H1-b, however, can I

start working on April 1st 2012 when my new H1-b is filed, under that AC21

H1b portability provision? Or will I have to wait until Oct 1st 2012 when my

new H1-b takes effect?

I read in earlier posts that you can start working on receipt of filing but will have to quit once you are approved, however, I have also read that you can file 2 LCA's one with an effective date of Oct 1st and another covering April1st-Oct1st. Is it possible.

I really want to join my new employer and not sure if they will want to wait until Oct 1st? Please help