DnD rounding always rounds task start to end of the day

Gantt
#1

Here is my config code.

gantt.config.work_time = true;
gantt.setWorkTime({hours : [8, 12, 13, 17]});
gantt.config.duration_unit = "minute";
gantt.config.duration_step = 1;
gantt.config.scale_unit = "day";

After I drag and drop a task, the start of the task gets set to 16:59 of the previous day, ALWAYS. Is this possibly a bug or how do I configure it start at the beginning of the work day.