[Honor 8 Guides, News, & Discussion] Wesley32:
First thing: before using this How-to guide. *I am not responsible for any data lost,bricked phones,or anything related to your Honor 8*

I am writing this from my own experience updating. Your mileage may vary.

Notes: I've heard reports that flashing stock recovery and stock boot.img from fastboot(instead of twrp) help to have a higher chance of getting past erecovery. Let me know if it helps.

To follow this guide you should be rooted,TWRP installed and using the B360 version while having the OTA available for B385 for FRD-L04.

Ok, lets get started.

Step 1:
Make backups. I made backups with HiSuite and within TWRP. Just in case.

Step 2:
Reboot into Recovery. I used TWRP v3.1.0-3 for steps outlined.
[URL="https://drive.google.com/open?id=0B0uzUjmZ9bI6eVBlWm1ZSE56Yzg"]Download for TWRP IMG[/URL]

Step 3:
You will need to [I]Unroot[/I]. Whatever method you want to use, do it,
but, I used the UnSU zip by Osmosis
[URL="https://drive.google.com/open?id=0B0uzUjmZ9bI6SXlmenpVM3Z4b0E"]Link for .zip[/URL]
Flash this .zip. Do not Reboot.

Step 4:
We need to flash the stock boot.img and the stock recovery.img. (This likely needs to be done in
Fastboot versus recovery)
[URL="https://drive.google.com/open?id=0B0zE1Kk8sIB6MDF6SmEyaXYzVTg"]Stock Recovery.img[/URL]
[URL="https://drive.google.com/open?id=0B0zE1Kk8sIB6NlIzOWJkQ1Z1OHc"]Stock Boot.img[/URL]

Now, Move these somewhere on your
phone (internal storage/SDcard) and go to Install from TWRP. (Many people
report success doing this step in Fastboot)
Locate files, Probably have to switch to Images.
Flash boot.img to [I]Boot[/I] and recovery.img to [I]Recovery[/I]

Step 5:
Shutdown phone from TWRP. Make sure when you turn your phone
back on, don't have it connected to USB.

Step 6:

Power up phone

Step 7:

You should be able to boot like normal to your previous phone configuration,
except now you have stock boot and stock recovery
and should be able to receive/install OTA.

NOTE: If you have issues with booting and it will only boot to
eRecovery, try hitting[I][B]Shutdown[/B][/I] and performing
a cold boot. If that still doesn't workthen you will have to run
through the prompts and recovery B360.That's why we have
backups as step 1

Step 8:
Once phone is booted, go to Settings-> System Update ->
Perform the update to OTA B385 like normal

Step 9:
We just need to get into fastboot mode now and flash TWRP
like we have done on B360 and previous.
Connect phone with USB debugging enabled and open cmd prompt.

to make sure device is connected

[I]adb devices[/I]

open directory you need

[I]cd c:\whatever the path you saved the TWRP.img[/I]

Reboot phone to bootloader

[I]adb reboot bootloader[/I]

Flash TWRP

[I]fastboot flash recovery twrp-3.1.0-3-frd.img[/I]

[I]fastboot reboot[/I]

Step 10:
After phone reboots. We need to get into the TWRP recovery we just flashed.
Whatever method you want to use. I just shutdown and used
power up+power button.

Step 11:
we need to flash Magisk to get root.[URL="https://drive.google.com/open?id=0B0uzUjmZ9bI6WFMwTUIwd21rX2s"]Magisk[/URL]
Place .zip on phone Sdcard or internal
in TWRP -> install -> locate Magisk flashable zip
[I]flash and reboot[/I]

I think that covers it. You should be updated to the latest B385 OTA and have Magisk root.

Sorry if this was long.

A ton of credit to [MENTION=3694505]Telperion[/MENTION] for helping and access to the correct files to get this completed