apt-get update
Get:1 http://deb.devuan.org/merged beowulf InRelease [33.8 kB]
Err:1 http://deb.devuan.org/merged beowulf InRelease
  The following signatures were invalid: EXPKEYSIG BB23C00C61FC752C Devuan Repository (Amprolla3 on Nemesis) <repository@devuan.org>
Get:2 http://deb.devuan.org/merged beowulf-security InRelease [26.5 kB]
Err:2 http://deb.devuan.org/merged beowulf-security InRelease
  The following signatures were invalid: EXPKEYSIG BB23C00C61FC752C Devuan Repository (Amprolla3 on Nemesis) <repository@devuan.org>
Get:3 http://deb.devuan.org/merged beowulf-updates InRelease [26.4 kB]
Err:3 http://deb.devuan.org/merged beowulf-updates InRelease
  The following signatures were invalid: EXPKEYSIG BB23C00C61FC752C Devuan Repository (Amprolla3 on Nemesis) <repository@devuan.org>
Fetched 86.7 kB in 2s (41.4 kB/s)
Reading package lists... Done
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://deb.devuan.org/merged beowulf InRelease: The following signatures were invalid: EXPKEYSIG BB23C00C61FC752C Devuan Repository (Amprolla3 on Nemesis) <repository@devuan.org>
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://deb.devuan.org/merged beowulf-security InRelease: The following signatures were invalid: EXPKEYSIG BB23C00C61FC752C Devuan Repository (Amprolla3 on Nemesis) <repository@devuan.org>
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://deb.devuan.org/merged beowulf-updates InRelease: The following signatures were invalid: EXPKEYSIG BB23C00C61FC752C Devuan Repository (Amprolla3 on Nemesis) <repository@devuan.org>
W: Failed to fetch http://deb.devuan.org/merged/dists/beowulf/InRelease  The following signatures were invalid: EXPKEYSIG BB23C00C61FC752C Devuan Repository (Amprolla3 on Nemesis) <repository@devuan.org>
W: Failed to fetch http://deb.devuan.org/merged/dists/beowulf-security/InRelease  The following signatures were invalid: EXPKEYSIG BB23C00C61FC752C Devuan Repository (Amprolla3 on Nemesis) <repository@devuan.org>
W: Failed to fetch http://deb.devuan.org/merged/dists/beowulf-updates/InRelease  The following signatures were invalid: EXPKEYSIG BB23C00C61FC752C Devuan Repository (Amprolla3 on Nemesis) <repository@devuan.org>
W: Some index files failed to download. They have been ignored, or old ones used instead.
root@grid:~#