According to Josh Grelle's August 19th, 2012 announcement on Facebook, he will be undergoing the process of switching sexes. "Josh Grelle" as we know him will soon no longer exist. On November 2nd, 2012, she announced her new name, Mina Marie Grelle.
This means since Grelle is switching genders, who will voice Akihisa Yoshii in Baka to Test to Shoukanjuu Spinout! – Sore ga Bokura no Nichijou (already separate episodes were included on the releases of S2 and it will air in 2013 as a full series) since it will air in 2013? Funimation's release of that series (which may be released in 2014 if they license it) may probably happen after Grelle finished the transition.
Grelle will still have the same voice and women play male parts all the time so my guess is aki will be voiced by the same person.
Grelle will probably play him again even if he/she switches sexes.
I knew he was a big brony, but never expected a sex change..
Still, it would not be wildly out of the ordinary for a girl to voice a boy character in anime. Especially in Grelle's case because hormones take a long time to kick in and a voice is very hard to alter in a period of only a couple of years.
He'll/She'll probably play Akihisa again.