BIOS M6500RC version 316 breaks OS boot using USB4

[alixolix]

Hi,

I have a problem that ASUS-Brazil can't help me. First of all, I use Windows and Ubuntu, Windows is installed on my internal SSD, Ubuntu is installed on external SSD accessed thorough USB4 dock. Unfortunately I had a bright idea :'-( 😭 ... I updated my laptop BIOS to the latest BIOS version, 316, after that I can't access my OS on my USB4 Dock anymore, I can access using USB3.2, but I lose bandwidth compared to USB4. ASUS-Brazil can't help me, even doesn't have access to ASUS development team to tell them to investigate or to make an opinion or suggestion about that. I attached an image with my setup and the message error. Please, can anyone help me?

[Falcon_ASUS]

@alixolix 
Do you remember the BIOS version you were using before? 
If the external device can be used when connected via USB 3.2, could you please provide me with photos of the connection method that works and screenshots of the system interface?
Thank you.

[alixolix]

Unfortunately, I don't know the previous BIOS version. I've even tried to force downgrade, but BIOS didn't allow. I use a mini cable type-C to type-A and connect to the USB 3.2, the photo provides visualization of the cable and the connection. Using Ubuntu through USB 3.2 until now works without any problems, the unique downsize is to lose USB4 bandwith, 40gbps dropped down to 5gbps.

[Falcon_ASUS]

@alixolix 
Since there are many BIOS versions for your laptop, if we cannot determine the version you were previously using without issues, we will not be able to clarify the differences between them. We apologize for any inconvenience caused.

[alixolix]

So is it possible to bypass the BIOS to downgrade the firmware?

and how can ASUS dev be aware about this situation?