Travel abroad after H4 Extension(I-539) Approval

USA L1, L2 Visa
1

Dear

Spouse’s H4 Extension (I-539) is approved along with my H4 Transfer and we have her I797 Approval notice with new I-94 card valid from Jan 10th 2014.
Current H4 Visa(stamped on passport) valid until Jan 20th 2014.

If she need to travel India in Dec 2013,

  1. Does she has to return the new I-94 while leaving USA?
  2. Does she needs to go for stamping if she plans to return after Jan 20th? if Yes, what are the documents required?

What if she plans to return before Jan 20th?

Thank you for your kind replies.

Cheers,
visa_nr

2

Please anyone can suggest on this.

Thank you in advance for your kind reply.