You can insert vertical markers called "separators" at specified times.
You can specify the following separator properties:
- location (date; required)
- color
- layer
- opacity
- width
See also DayPilot.Gantt.separators property.
JavaScript Example

gantt.separators = [
{
color:"red",
width: 2,
location: "2016-10-26",
layer: "BelowEvents"
}
];
DayPilot