Ubuntu – How to create and administer multi-architecture PPAs

In this context, the distribution field is irrelevant. Look in the official Ubuntu archives. Of course, you'll see that the top changelog entry will have "unstable" as the distribution for many packages. Likewise, all uploads that make it into the updates repository are actually copied over from the proposed repository. So a package in maverick-updates will actually say maverick-proposed in the changelog.

The importance of the distribution field depends on the tools that make use of it. For instance, if you use dput to upload to your PPA with: ~<your_launchpad_id>/<ppa_name>/ubuntu/ the distribution field in the changelog determines for which release the package will be built. But even this can be over-ridden by uploading directly to release you want with:

~<lp_name>/ppa/ubuntu/<ubuntu_release>

Launchpad's build from branch service uses the ability to copy a package from one PPA series to another. It doesn't actually care what is in the changelog for this. So the way you are currently doing things is correct.

Yes and no.

There is currently no way to use dput to upload a package that builds for multiple Ubuntu releases. However, you can accomplish your goal using one of these two methods:

Create a Recipe

If you are building a package from a branch on Launchpad and you have Debian packaging, create a daily build recipe that targets the Ubuntu releases you wish to support. This is described in more detail in the latter half of this answer.

This is really the best solution since it also automates new builds every time you make a change (with a limit on one automatic build per day, although you can manually dispatch additional builds).

Upload Multiple Builds Manually

This is not an ideal solution - but it works. What you need to do to make this work is:

• Adjust the version number in the changelog to match this format:

  [version]-1ppa1~[release]1
  

  ...where [version] is the package version and [release] is an Ubuntu release codename (like trusty, saucy, etc.).

• Make sure the changelog is set to build the correct release. In other words, for Trusty, the first line of your changelog should look like this:

  ffc (1.3.20140513-1ppa1~trusty1) trusty; urgency=medium
  

Upload the package using dput and then repeat the two steps above for each release you want to upload packages for. You can see an example of how this works here.