So, I received my AM6 Plus a couple of days ago. It came in an official (green) AM6 Plus box, had AM6 Plus on the device sticker but during boot I only saw a S922X logo (without the J) and in CE the CPU was listed as Amlogic S922X rev b. Furthermore, the CPU freq was 1.8GHz. So I mailed Ugoos about this and they promptly replied:
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Hello,
Kindly please now, all boot logo of AM6, AM6 Pro and AM6 Plus are showing S922X same as CPU. But it will be different for the board when you open the case.
For CPU colock speeds, Amlgoic had replied to us, they mixed other OEM client orders. Our Ugoos AM6 Plus S922X-J should be with 2.2Ghz, but Amlogic sent one small batch with another version 1.8Ghz S922X-J for us. In order to avoid any misunderstanding caused, we already informed our all resellers in Aliexpress or any other platforms, let them explain and help to deal with the compensation about this mistake. However, we make sure this mixed batch 1.8Ghz s922x-j also included Dobly vision and audio license.
If you meet this problem, I will suggest you to show the shop seller with an image to show the Serial number on the setting part, as we can track the AM6 Plus if it is the batch Amlogic mixed by Serial number, thanks.
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I opened the box and lifted the heatsink… it is indeed an S922X-J…
I contacted the reseller but haven’t heard from him yet.
A53 cores shows 1.8 GHz for both rev. A and rev. B in CE
If you have rev.b then it works on 2.2GHz
It also shows 1.8GHz in Ugoos hardware monitor in Android.
It’s probably a fail safe OS value to work on rev.a and rev.b version. With rev.b you can raise it up to 2.2GHz
You’re right.
I installed CPU-Z and it shows A53 cores run at 1.8GHz and A73 cores run at 2.2GHz 
I’m trying to get dual boot emmc working on the Ugoos AM6 (2GB/16GB) that a friend now use, until now it’s been on latest slimboxtv (0.5.4 firmware) with Kodi and PM4K, which works OK…on my AM6B+ I dual boot both no issues.
but this one is strange, it won’t let me boot CoreELEC from USB/microSD or CoreELEC app which works on AM6B+, it just says updating and bootloops, but when I use the old Ugoos dual boot 0.2.8+ firmware I can boot no issues, the problem is when using that firmware is that CoreELEC build is from 2020 and it won’t let me move the install to emmc as I get error messages about can’t creating the CE partitions (something like that), I can’t even remove Android and go for single installation.
I tried flashing the 0.5.4 dual boot firmware but it just stops with error message with USB burning tool, I can only flash the old 0.2.8+ dual boot firmware and slimboxtv…when updating the 0.2.8+ build with the 0.5.4 OTA zip it does update but then I don’t get any HDMI signal, is there anyway to get this working or just go back to slimboxtv and be happy haha.
Did you try flashing a normal (i.e. non-dualboot) firmware yet? Normally if you want the CEEMMC tool to transfer CE to EMMC you should not already have a CE partition on it.
I can’t get CE to boot when having slimboxtv firmware installed, works fine on the AM6B+.
I was talking about the normal non-dualboot firmware from Ugoos itself, not Slimbox.
no, but slimboxtv is basically Ugoos stock firmware 0.5.4 with TV UI, I mean it works on the AM6B+. 
Maybe try the re-release 054n, also 054n2, from Ugoos download.
Then boot CoreELEC from external
Then ceemmc-x…etc