I have a surface pro 6 connected to a UD-3900 docking station, then 2x iiyama XUB2792QSU-W1 monitors connected via their hdmi ports. (HDMI -> HDMI, and DVI -> HDMI). the max resultion selectable in windows is 1920x1080 on each of the monitors.
We thank you for posting your solution to use the UD-6950 to achieve your desired resolutions of 2560 x 1440 for your dual monitors. If you have any further questions or concerns please let us know and one of our support specialists will be happy to help!