ubuntu-advantage is a canonical support client thing. doesn't apply to neon, it should be dropped from the ISO.

on iso because of minimal seed it seems

ubuntu-advantage-tools | ubuntu-advantage-tools | Neon.Bionic minimal seed          | Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>      |           16636 |              74

Needs manual mangling via livecd-rootfs or a build hook in the tooling. ubuntu-advantage-tools is pulled in via deboostrap, so it is there long before apt dependency considerations kick in.

• apt install neon-ubuntu-advantage-tools to replace the actual ubuntu-advantage-tools
• apt-mark auto neon-ubuntu-advantage-tools
• verify the original package is being consistently replaced