[OnePlus 8 Questions & Answers] intheb0x:
I'm sorry I didn't see your post until now, I'm actually in the process of messing with the mbns currently.

What I think I'm going to do first is try to find a MBN file from like an s20 ultra or something similar for Verizon that is normal and has 5G activated as normal.

When looking at carrier policies on Android 11 before updating and such, carriers like AT&T on the OnePlus 8 would actually have 5G working normally, but once you updated to Android 12 5G was removed in the carrier policy I think it actually states due to a request from AT&T.

Other carrier policies such as T-Mobile which this is a T-Mobile device was like the AT&T carrier policy in Android 11, it was very small lacked basic , it was very small. It basically didn't have anything in it because it was meant to have the device wide open unless requested by the carrier.

Messing with certain files I was able to get the 5G indicator back using a spectrum SIM on the OnePlus 8, and it says override network is NR_NSA.

So it's definitely there and it definitely sees it, looking at certain messages in QXDM and similar it seems to have all sorts of error codes and such You know the RRC messages and all that stuff.

I still don't have the device rooted and I'm actually close to getting rid of this device well I'm going to keep it but I'm going to upgrade.

But I guess I'll keep playing with it for the meantime I'm pretty much like 60% there enabling NSA connection with Verizon I mean I get the 5G indicator I get the 5G status in cell mapper and net monster, when before just a normal MVNO or Verizon SIM would give you 4G Plus or LTE CA and no 5G available or anything 5G related. I'll post some pictures so you know what I'm talking about what I'm seeing.

I don't know anything about the signature verification and I didn't think about it but it makes me wonder if I do replace the mBN file that there's going to be some type of error code or something else in related to that? Or signature verification? I don't know but I'm still willing to play and try at least I think that's what I'm hung up on.

I'll give you the code of the item I change in QPST / Qualcomm tools PCAT. Once I get home I think it's 74611 or 71461 it's in MM mode and what it is is it's a disable or enable option for using the NV to figure out what bands and what capabilities are needed instead of the sim.

It's basically you just disable it if it's enabled or vice versa, after doing that you will then have 5G indicator immediately just like 5G is available. Obviously if you are in an area with 5G and such. But like I said the mbN files on the OnePlus 8 or any device that's not " capable " on their network will have that language in it and there's at least four or five different spots in the mBN file where it actively disables 5G connectivity.

The old trick of enabling 5G via carrier policy in Android 11 stopped working sometime early 2023 and I would assume that had to do with Android 12 and up, that trick still may work if you're on Android 11 because I know for a fact you will get 5G on AT&T on Android 11 even though the device isn't white listed.

I'll post pictures after this post.