Today I tried upgrading my Ubuntu Mate Linux virtual machine from artful (Ubuntu 17.10) to bionic (Ubuntu 18.04) and the upgrade went ok, apart from one issue. It seems that asi-common is not available for bionic. I searched online for the package but cannot find it so I assume this is part of the mutlaqja ppa. Does anyone know why this package is missing?

Indeed the package originates from the mutlaqja ppa:

$ apt-cache showpkg asi-common
Package: asi-common
Versions:
0.8.0+r3461~201710091055~ubuntu16.04.1 (/var/lib/apt/lists/ppa.launchpad.net_mutlaqja_ppa_ubuntu_dists_xenial_main_binary-armhf_Packages) (/var/lib/dpkg/status)
Description Language:
File: /var/lib/apt/lists/ppa.launchpad.net_mutlaqja_ppa_ubuntu_dists_xenial_main_binary-armhf_Packages
MD5: bc9a68ff9d55817ae5b0965c03e7e657
Description Language: en
File: /var/lib/apt/lists/ppa.launchpad.net_mutlaqja_ppa_ubuntu_dists_xenial_main_i18n_Translation-en
MD5: bc9a68ff9d55817ae5b0965c03e7e657


Reverse Depends:
indi-asi,asi-common
Dependencies:
0.8.0+r3461~201710091055~ubuntu16.04.1 -
Provides:
0.8.0+r3461~201710091055~ubuntu16.04.1 -
Reverse Provides:

Should be available within the hour, thanks for the report!

Fixed indeed: indi-full is not being uninstalled anymore when upgrading to bionic. Many thanks!