Originally Posted by Daytona675tr
I have a galaxy a8 2018. I dont know what is this number i see always forum
A530f U6 or U9 or U11 ?? What is this U6 U9 ??
U* relates to the bootloader (BL) version you got in your stock firmware.
It is known for being well protected, I'm not sure you can downgrade it, so avoid stock upgrades if possible, as the BL will be upgraded too!
You can see it in the name of the rom image (and in many other ways), example:
U8 = bootloader v8