@aibd yes, chrisrg suggested this and I’m keen to try it. I’m still trying to salvage a couple documents before I give up on my data 
@chrisrg @aibd Just a quick update. I unpacked the .bin file last night and manually ran fastboot flash boot_a boot.img etc. etc. I managed to get into /e/ OS, but after I logged in the OS crashed back into the bootloop again. I installed on both slots a/b and set active partition etc. I’m flogging a dead horse at this point. Time to re-flash stock Android.
Thanks again for all your help!
Well, you got a bit further. Shame it didn’t get you to your data though. From memory there are some other files that are in the os zip apart from the payload bin, don’t know whether that would have a bearing on it at all. A few days ago I did a similar thing on a oneplus phone and ended up with an almost bricked device that would not boot into anything: black screen in edl mode. Got it sorted eventually but that meant a lot of mucking about in unfamiliar windows. Driver problems, constant update prompts, it just doesn’t leave you alone!!
Anyway, you shouldn’t have any of that sort of trouble getting stock flashed. Fingers crossed you don’t find any hardware issues when you boot into google and can proceed back to /e/.
Good luck and let us know how it goes.