On May 31st, he tweeted a message to fans saying "I guess you waited a week for me. I've come back very safely. I was very touched seeing all the messages of support I didn't get to see in the meantime. Anyway, I really miss you."
So glad to hear that Hyungsik returned safely. Kim Soo Ro, on the other hand, ended up suffering an injury while filming, but like a trooper...he went back to filming shortly after a trip to the hospital.