HP EliteDesk 800 G4 Workstation Edition (TWR) - Group Policy / Admin Blocking BIOS Update

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Hello all,

I purchased a HP EliteDesk 800 G4 Workstation Edition (Tower) recently and had the following chain of events happen:

• First powered the machine up and it started immediately to perform a BIOS update, even though it wasn't connected to the Internet. I let this update run and completed installation.
• Once completed, I got into Windows and downloaded the latest BIOS update for the machine and the HP program showed that the currently installed version wasn't the latest and advised to proceed with an update, which I did. This gave both the options to 'Update' (I have seen this option blocked out for some people but not for me at this stage) and to 'Create a Recovery USB Flash Drive'.
• After choosing 'Update', the machine rebooted and I got a message saying that 'Group Policy' had blocked any BIOS updates to the machine and then a further message said that the Admin had chosen to lock the current BIOS version.
• Assuming this was just a setting that needed disabled, I went into the BIOS settings and I did see the option for the Admin to lock the BIOS version but it was unchecked. I reset the CMOS both via the physical button on the motherboard (with power disconnected) and also from within the BIOS, where I chose to restore factory default settings.

One of the strangest things about the initial BIOS installation (on first start-up) is that it was for a System BIOS version of "Q01 Ver. 02.18.00 12/27/2021". From my reading of the BIOS files released for the WS Tower version of the EliteDesk 800 G4, there was no "02.18.00" BIOS update. There is, however, a  "02.18.00" BIOS update for the SFF version of the EliteDesk 800 G4 and I'm wondering if the seller has accidentally flashed the wrong firmware onto the motherboard?

To try and cut to the chase...I managed to go to the "Check HP.com for BIOS Updates"  option within the BIOS and it detected and installed the latest version that I was looking to get (02.21.00). Success. However, whilst I know there are currently no more BIOS updates available, when I try to select the 'Update System and Supported Device Firmware' option in the BIOS, this 'Group Policy' message appears again saying that it has been denied and that the Admin has locked the BIOS version, as before.

I did look into these error messages generated for the Group Policy block on the BIOS updates and it appears to be generated (mostly) from people who are trying to rollback their BIOS version (which I know is blocked by HP on some machines) but I can't understand why now, with the latest and correct version of the BIOS installed, that I'm still getting this message.

Is there an obvious setting I'm missing for this Group Policy issue? Apologies for the very long message but the topic is very broad / vague without the context.

Appreciate any help.