Are ubuntu archive mirrors tested daily by ubuntu/launchpad?

[Savvas Radevic]

Are the ubuntu archive mirrors (e.g. cy.archive.ubuntu.com) tested
daily for errors by ubuntu/launchpad scripts?
I mean errors such as this one:
https://bugs.launchpad.net/ubuntu/+source/update-manager/+bug/525608

Sorry if it's the wrong place to ask this, but I tried on launchpad
and it expired:
https://answers.launchpad.net/ubuntu/+question/102188