(...)
Err:6 https://dl.bintray.com/aluxian/deb <channel>/main amd64 Packages
  404  Not Found
(...)
W: The repository 'https://dl.bintray.com/aluxian/deb <channel> Release' does not have a Release file.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: No s'ha pogut obtenir https://dl.bintray.com/aluxian/deb/dists/<channel>/main/binary-amd64/Packages  404  Not Found
E: Alguns índex no s'han pogut baixar. S'han descartat, o en el seu lloc s'han emprat els antics.