My OPT expires on May 31, 2009. My H1B is approved starting Jun, 1, 2009. I am going back to China from May 10-May 23. Does anyone know if it's risky to come back on OPT (I already has a F-1 visa valid till May 31, 2009)? Or should I get a H1B stamp while I am in China? I only go back for 2 weeks. I don't really want to waste a day in US embassy. Thanks a lot.