Looking at the storage/logs folder I see acorn.log and atop is
[2021-02-18 21:18:31] production.ERROR: The /code/wp-content/themes/btc/bootstrap/cache directory must be present and writable.
This tells me that I potentially need another step in my setup for Pantheon to symlink this cache folder to the uploads folder as I have done for the storage/folder. There is no mention of this bootstrap folder in the Sage 9 docs (duh I know but I looked), it’s not in the theme structure, and not much on the Acorn github about this folder needing write access.
I am not sure adding this symlink will automagically make Acorn happy or if I’ll need to do something else to kick start acorn. Maybe this is the source of my issues? I’ll report back after I’ve made this change, and updated my methods.