The earliest one can get EAD card under EB2 (while pending i485) is 11-14 months from the time of prevailing wage determination application provided it is not audited. So h1b napareko condition ma if the employer is ready to eb2 filing and opt is valid for so many months, eb2 is a good idea. But if opt is expiring in few months and STEM extension is not applicable, going to school is the best.