He's been summoned to enlist on March 12. The idol purposely held his wedding ceremony with Min Hyo Rin before he was to enlist, knowing he would have to enlist sometime in either February or March. 

SEE ALSO: K-netizens say BABYMONSTER's Ahyeon has the potential to become the next Jennie

[UPDATE] YG Entertainment has confirmed that Taeyang will be enlisting according to his mandatory military enlistment summons on March 12. He'll be enlisting two weeks after G-Dragon.