Hi,That's actually not something that anyone has tried to my knowledge. If you intend on upgrading to A12, I have an idea you can test if you're willing? The worst that happens is that you'll have to wipe your phone - which currently seems required anyway. Do you want to give it a try? I'll give you instructions if you do.
I will also answer @Homeboy76. My mobile is a pixel 5.
I made myself at the idea of wipe my phone, I made backup of my apps and data.
Yes I want to try, I also think using the method with Android Flash Tool.
As long as I do not make bootloop or brick.