Well what did I know?  Support Assist updated the BIOS to version 1.8.1 dated 14-Sep-2022 and with no other changes made to they system/dock wake from my WD22TB4 now works after any amount of time!  I could not see this "bug fixed" it the release notes but it works:-).  Peter 
I've received my XPS 13 Plus 9320 running Windows 11 Pro 64bit (build 22000) and WD22TB4 Thunderbolt Dock connected via USB to a wired mouse/keyboard. Latest BIOS (1.4.0) and drivers all installed. When the PC sleeps I can't wake it from the Mouse or Keyboard connected through the dock. If I reach over and press the XPS keyboard everything works fine - but it is a pain:-). I have unchecked "Allow this computer to turn off this device" power management options in all USB devices and where it is not greyed out checked the "Allow this device to wake the computer" option.  Still no luck! I have had a response from Dell advising to "Disable “Deep Sleep Control" which also stops you having "Fast Start" and this does work, but this makes the start-up and other options slow/clunky! Any other options to allow wake from keyboard/mouse please? Thanks, Peter 
XPS 13 Plus 9320, WD22TB4, wake issue