Travelling outside the USA while on Optional Practical Training (OPT)

[ravirajesh574]

I have a friend who is in a STEM OPT. His OPT is ending on 15 June, 2018. He is travelling outside the USA on 21 April, 2018 and coming back on 15 May, 2018. Will there be any issue at immigration while he comes back to the USA, since he is just left with one month of his OPT? His Visa is valid till 2019.