Question about Dell WD19

Dell writes that the dock supports 1xQHD@60 via HBR2 and 2xQHD@60 via HBR3. (HBR2 or 3 must be supported by the laptop).
That would optimally be 1440p@120, although it doesn't say anywhere whether that really works on a monitor.
Source: https://www.delltechnologies.com/resources...