Green card eb-1. But turning 21 before green card issue.

[Jk Subhash]

So my mom is working in L1 visa and I'm here in L2 visa. We have applied for green card. Priority date 24th July 2016 through EB 1. But I will be turning 21 on August 4 2017. I'm currently studying.
What are my options if the green card is not issued before I turn 21??
Should I apply for F1 or should I take advance parole and be at my country till I get green card?? Is any of this possible or any other option??