apt - SrFatCat/LinuxHelp GitHub Wiki

N: Repository '***' changed its 'Version' value from '' to '**'

sudo apt update --allow-releaseinfo-change

... Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.

sudo apt-key list

Warning: apt-key is deprecated. Manage keyring files in trusted.gpg.d instead (see apt-key(8)).
/etc/apt/trusted.gpg
--------------------
pub rsa4096 2017-10-23 [SC]
D89C 66D0 E31F EA28 74EB D205 6192 2AB6 0068 FCD6
uid [ неизвестно ] Launchpad PPA for Janek Bevendorff
...

apt-key export 0068FCD6 | sudo gpg --dearmour -o /etc/apt/trusted.gpg.d/keepassxc_key.gpg
sudo apt-key --keyring /etc/apt/trusted.gpg del 0068FCD6