Bug - Driver switches display to HDR from Vulkan PQ swapchain but keeps 8-bit display link when windows is in SDR mode

I’m developing a Vulkan app on Win11 and I’m currently testing HDR behavior.
My app lists modes supported by the driver with Vulkan and chooses from that list what it wants to render.
I validated that everything works as expected when rendering SDR when Win11 is in SDR mode, and when rendering HDR when Win11 is in HDR mode.

The issue occurs when the driver still lists HDR modes when windows is in SDR mode. In that case, the driver triggers a mode switch to HDR when my app chooses a HDR swapchain, and noticeable banding occurs, since the display link is at 8 bits.
This issue occurs BOTH when my app is in windowed mode, and when it’s fullscreen borderless mode (I checked with PresentMon that my app is using the HW Flip mode).

Since my app is sending a RGB10A2_UNORM buffer to the driver, I think it’s a bug that the display link is still in 8bit per channel mode, when I’m running fullscreen.
It’s also strange that this behavior is present when I’m running in windowed mode, since Windows does compositing and is not aware of the HDR content of my app.
Additionally, if I manually force the display to be in 10bits per channel in the NVIDIA driver, but keep Win11 in SDR mode, the banding goes away.

I tried using an HDR scRGB swapchain when windows is NOT in HDR mode, and it turns out that in this case windows switches to HDR mode.
So I guess the issue here is that when using RGB10A2 in HDR mode, the driver isn’t switching windows to HDR mode when it should.

OS: Microsoft Windows 11
Card: NVIDIA GeForce RTX 2060
Driver Version: 551.86 Game Ready