The rumour mill says that parts of Canonical's infrastructure are being DDoSed. That being said Canonical did maintenance on their PPA infrastructure 2 days ago according to their Mastodon page[0]. If it is an attack maybe this is an attempt to stop people being able to cleanly upgrade to avoid the Copy Fail / algif_aead issue?
tankenmate•1h ago
[0] https://ubuntu.social/@launchpadstatus