Can a US citizen be replaced by an L2 Visa holder in a job in the US?

I agree with my colleagues. It depends on the circumstances.

I have an A# number from when I was on OPT. Is this the same I should use to fill I485 adjustment of status package?

Yes you should use the same A number although it may be changed. I highly recommend that you consult an attorney to review your paperwork before...

I am on CAP-GAP, can i transfer to different school as my H1B will be withdrawal and join same employer on CPT frm dif'nt school

You need to consult your DSO.

As long as the payment is for work that was authorized it should be okay. Consult an attorney.

Would i be approved if my priority date becomes current?

There is no waiting period for the spouse of US citizens. You need to consult an immigration attorney.

Do Affidavits need to be notarized? and do they have to come only by people you have interacted after marriage?

It always give an affidavit more weight if it is notarized. Yes your family can write about their personal knowledge of the relationship.

Hello My husband was deported last year in August he is now in mexico and I would like to know if I can still petion him

You can file the I-130 but need to know what was the reason he was deported. Consult an attorney to assist you.

I have a F1 visa and I am engaged with an USC for a year and 4 months already. Can we get married without changing my status?

There is no requirement that you must change your status when you get married. It may difficult for you to re-enter the US on a F1 if you are...

Can I step down from Full time work, to Part Time work on a L1A Visa

I would not recommend it, but it may be possible. You need to consult your employer's immigration attorney.

Today i had my FB1 immigration visa interview but they put me in AP in islamabad my petitioner was my mother and i m unmarried

People from Pakistan are put in AP because the consulate needs to conduct background and security checks.