LPR stay outside US for more than 6 month

[Anand.sankaran]

I have applied i824 for my son who born outside the US before we got the Green Card. It look like, it will take 6 to 8 months for processing the i824 application.

Sine i have to support my family, i am planning to level US for 6 month to 1 year until complete of  my son's i824 process.

Kindly let us know do i have to apply reentry or AP (i131 form) before leaving the US in this case.