Flashed board firmware with IDT, can't figure out how to update from there

[chanceh]

As the title says, I followed the instructions in this post (BND-L24 Board Firmware | IDT Flash Software) and I did so successfully, at least as far I can tell. The phone boots into EMUI version 2 and Android version 4.3 (build HL1BNDMAA001064).

My goal is to get back to stock Oreo, but I can't seem to figure out how to do that. Aside from my inability to find the correct firmware (BND-L24 8.0.0.359 C567 was the version that was running on my phone prior to me breaking everything, but if I can't find that, the question about being able to flash images from the other Honor 7X models becomes relevant, see this post that has gone unanswered as of writing), the partition table changed (e.g. from recovery and recovery2 to recovery_ramdisk) somewhere before or in the Oreo update, so I can't just extract the images from an appropriate update.app file and flash them. Do I need to go through Nougat first? Can I completely wipe the existing partitions to cleanly flash a full OTA?

Is there a viable path to get my BND-L24 back up to a modern stock version? Any insight would be greatly appreciated; let me know if more information would be helpful. Thanks and take care.

 

[chanceh]

Edit: I found success by downloading https://androidhost.ru/2zON [BND-L21 8.0.0.330(C636) ministryofsolutions.com], putting the extracted dload folder on a flash drive, plugging it in to the phone with an OTG cable, and starting the update through the "Software Update" app (which provides a "Update from SD card" option (I guess it also counts OTG storage?) that is included with the super-old ROM that the board firmware flash and subsequent update provides.