No members of SS501 sent him off as Hyun Joong and Hyung Jun are both busy filming their drama, Jung Min is busy with his musical and Kyu Jong is still serving the military. Park Ji Bin though is there to greet him and send him off.
Here are few of the photos of Young Saeng with his new military hair in which he said on Twitter that he still is not used to.
Here is video courtesy of shirbogirl21 that I lifted from here
ShirboGurL6 YouTube channel of Young Saeng talking before enlisting.