UP2720Q, calibration issues

To receive assistance from Dell support agents they need to first verify the ownership and warranty status. Click the blue "Get Help Now" on the right to start a private live chat session. Share the private Service Tag with them.

Go HERE and enter the private UP2720Q Service Tag. That will show you when it originally shipped/invoiced and the warranty status.

Enter the Menu- Others to see the current firmware version. What is it?

@DELL-Chris M​ There is no way to contact support for this problem on their support page.  Unless its one of their 4 pre-determined faults then they take you to a problem solving page otherwise their is no options for this.

There are several misunderstandings or false claims in your post. Let's clarify them:

-Your Benq monitor or a dell monitor that claims to be HDR are not "HDR" displays, they accept HDR signal (rec2020 PQ) and transforms those RGB numbers in that encoded colorspace to the limited SDR (1500-1000:1 contrast ratio) and limited gamut (at best union of AdobeRGB and P3) of your display panel.
This is a very common misunderstanding about what HDR is.

-If OS says that display to GPU connection is 8bit it can be due to your GPU or GPU driver limitations. Resolution x refresh x bitdepth = bandwidth.
Since you prove no info about that, nobody will help you without that info.

-About colors. UP2720Q is a widgeamut monitor with HW calibration, hence in the same way as any other widegamut Eizo, NEC... etc, using the widest native gamut presets WITHOUT color management will result in oversaturated colors.
As in ANY OTHER widegamut monitor if you use display with a color managed enviroment and with a display ICC profile that matches ACTUAL display behavior, it should behave as intended.
By default Windows desktop is not color managed, but windows apps like Firefox, Edge, Photshop or Lightroom can effectiverly use display ICC profiles. By default macOS desktop is color managed but the ICC profile compatibility is limited to the simples ones (matrix type, single curve, fake infinite contrast).
Driver ICM profile instaled by Dell driver or macOS default color profile created from EDID are generic profiles that describe display in ITS NATIVE GAMUT (only valid on those OSD presets) and assume factory white point to be D65 and TRC/gamma sRGB/2.2. If it does not behave like taht your should prove by measurement.

-UP2720Q does not use old DUCCS calibration software. To use its HW calibration features you'll need "Dell Calibration Assistant for Windows OS"
https://www.dell.com/support/home/en-us/product-support/product/dell-up2720q-monitor/drivers
An example:
https://photographylife.com/reviews/dell-up2720q
Extensive validation of results can be done with an external colorimeter like i1displaypro and DisplayCAL, laike in any other display with or withput HW calibration. Vendor software validation is usually extremely limited.

As general recommendation, people without a minimum understanding of color management should avoid widegamut displays... although we may exclude from this list "P3" common/multimedia displays used with macOS, as long as user assumes 1) that they should not change OSD mode 2) that factory whitepoint is more or less on the spot.