This is already out of scope for the bug report, but still leaving a note here that I filed https://salsa.debian.org/debian-keyring/website/-/merge_requests/17 in an effort to help others avoid having keyring update attempts fail.
- Bug#1140801: Acknowledgement (bookworm-pu: package xz-ut... Otto Kekäläinen
- Bug#1140801: Acknowledgement (bookworm-pu: package ... Adrian Bunk
- Bug#1140801: Acknowledgement (bookworm-pu: pack... Otto Kekäläinen
- Bug#1140801: Acknowledgement (bookworm-pu: ... Otto Kekäläinen
- Bug#1140801: Bug#1140702: Bug#1140801: ... Jonas Smedegaard

