in packages/timebrush-powerbi/src/TimeBrushVisual.ts [199:208]
private boundRangeByItemDates(range: [Date, Date]) {
// Bound the range to actual available dates
range = <[Date, Date]>this.getRangeBoundItems(range).map(n => n.date);
// If the selected range is just a single item, then offset the final dates a little bit to create a brush
if (range.length === 2 && range[0].getTime() === range[1].getTime()) {
range = [new Date(range[0].getTime() - 1), new Date(range[1].getTime() + 1)];
}
return range;
}