It looks like the impeachment ruling by the ROK Constitutional Court will be issued by March 13th. If the impeachment is confirmed a new election will happen up to 60 days later which means early May could see the next Presidential election happen:
Park Han-chul, Constitutional Court chief justice
Constitutional Court President Park Han-chul said Wednesday that the court should make a ruling on President Park Geun-hye’s impeachment by March 13.
The call for a speedier decision reflects concerns that the impeachment trial might not be completed as two out of nine justices are soon to retire. [Korea Times]