Hi,
With reference to this thread, Celerway Cirrus CWY-M2.1-E5L2W1
Could this hardware be supported in any way? It's already running any form of OpenWRT since this string is seen in configuration a few places.
I have tried to flash it with Mediatek AP-MT7621A-V60 EVB and MediaTek MT7621 EVB and it then newer came online again.
Welcome to the community!
In the future please recall not to use a firmware that's not made for your specific device. As you see, you risk bricking your device.
But with that said, the second and third post in the thread you linked clearly stated your device is already supported. The information to the correct firmware is on the thread you linked.
Thanks,
Not so worried about bricking the unit, it's useless in the current state, and I have 22units that I either have to work or replace them with something else. I also know the recovery procedure and have the original images and there was no problem returning to original firmware 
That thread actually refers to a different architecture, MediaTek MT7620A ver:2 eco:6 while the router I have is MediaTek MT7621 ver:1 eco:3 so I'm curious if there is possible to find any other router that matches.
I have tried the search function, but could not find any matching there..
Can you use ssh or serial to get a CLI on one running the stock firmware? Or even examine the boot log with the status page.
Don't just blindly try different firmwares but if you can find a model with the same partition table it has at least a chance of working. Use serial to boot the OpenWrt initramfs first.
If you look inside the box you may find clues that it is just another rebranded ZBT.
