Can we get a xenial update? For libmbim and libqmi (different maintainers, I know)

I suggest you report a bug. If the bug and security fixes are significant then the package will be updated sooner rather than later.

Ubuntu is not a rolling release distribution and packages are left if there is no significant difference in the versions. This is especially true in the LTS releases where stability is champion.

the PPA https://launchpad.net/~aleksander-m/+archive/ubuntu/modemmanager-xenial might help.

The PPA might help.

The issue is apparently well known: https://forums.lenovo.com/t5/Linux-Discussion/ThinkPad-X1-Yoga-LTE-Sierra-EM7455-on-Linux-Ubuntu-16-04/td-p/3344299/highlight/true

sudo add-apt-repository ppa:aleksander-m/modemmanager-xenial
sudo apt-get update
sudo apt-get upgrade

Should do it (Using Manfred's link)

Yeah, that PPA works, but that is just not the question being asked here.

LTS stands for long term *stable*, which means *bug fixes* are something one would expect to make it into those versions. New features, less so. Apparently (see link above, I did not verify), the new version includes a one liner bug fix for a well known issue with my kind of modem.

Now I don't care if you backport the bugfix or build the latest release, but we're talking about a small but *significant* change that improves *stability* (i.e. "hardware support works") in a long term *stable* version.

The next person to tell me anything else is basically telling me LTS is a meaningless label, and I should use a different distro with a different support model.

That's fine, by the way, that's your decision to make. I won't comment any more after this. But so far, this conversation was a little surreal of the "it's not a bug, it's a feature" kind.

Then report the bug.... If it is significant then the package will be updated sooner rather than later

As said by yourself: "LTS stands for long term *stable*". This means that updates to existing packages are done only in exceptional cases, e.g. for significant improvements or to fix severe bugs.

If the current xenial versions of the packages libmbim, libqmi and network-manager have a weakness that renders them unusable on a certain family of systems, then this is (at least in my opinion) reason enough to provide package updates.

I suggest that you create a bug report with such request.

Nice customer focused attitudes on display here.

That solves my problem, another distro it is.