iCloud and the keychain stuff it supports is just about the buggiest pile of junk I've seen from Apple. Some days it logs me out a few times. I thought originally it was because I had a really old mac.com address I used for it, so created a new one with a different domain, but it's still hopeless. Just as well I have all my passwords stored in LastPass, because I can't rely on keychain providing them to apps that think they've saved info. Honestly, at this stage, I would run a mile before implementing "Sign in with Apple" in an app, because my experience of AppleID leaves me thinking I'd be deluged with support requests for something I couldn't resolve.
Meanwhile, more pertinent to the thread, in this thread I posted a shell script, which is what I usually use now to upload to AppStore Connect. At least I know, since the app-specific password is in the script, that I'm not going to open Transporter and find my credentials missing again.
In case anyone else runs into this (my Mac auto-updated this morning), here's how to do it: First, after you've built the code, find the directory where your ipa file is; since my username in B4i is set to nigel, and the build server is in my Downloads folder, it's a case of cd...
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