Much of the software that TurnKey provides actually comes from the Debian software repositories. That is the case with OTRS.

There are pros and cons to doing that. The primary downside is that the software is often "old". DUe to Debian packaging policy unless under specific circumstance; once software is accepted into the the Debian "main" stable repository (actually it's during the testing freeze to be precise) that version of that particular software does not get updated. This means that packaged software can often be years old.

The plus side of that though, is that makes Debian rock solid stable. All the moving parts have been tested together so (usually) everything "just works"! Security fixes are backported to keep the software secure. Because the software is patched without updating the version, you can be assured that the security updates are safe and generally don't break things. To be fair there have been edge cases where stuff has broken, but that is usually when the effort to backport security patches is too much so a newer version is introduced. Because of this we enable auto security updates by default.

That means that while we use software from the Debian repos, you can generally "set and forget" it. If you install software from upstream, you then need to monitor for security updates and manually install them each time they come out (and possibly deal with the results if something goes wrong).

So generally if software is available within the Debian repos we'll use it. Although we will consider using upstream (non-packaged) software if there is a good reason (e.g. perhaps the software is ridiculously old and missing important features? Perhaps there are significant bugs which have been fixed in newer version?) Obviously if it's not packaged then that's a very good reason! :)

So short answer to your question is, no we don't currently plan to update the version of OTRS within v14.x. I see that Debian testing currently has v5.0.x so v15.x will most likely have that version.

When we release v15.0 OTRS appliance you can then decide whether you want to upgrade your existing server (there may be some v15.0 features you'll need to manually include if you want them). Or use TKLBAM to migrate your data and then make adjustments as need be to ensure that everything works as it should. The beauty of the second option is that you can test the migration in a VM first to make sure everything is exactly as it needs to be before you do the upgrade "for real".

If you really want to upgrade to the latest version of OTRS then that's fine, but I'll warn you now that it will be a bit of a pain. Debian packages have to comply with the Debian packaging policy and the Debian file hierarchy system so files (including user data etc) will not be in the same places as it is in a default upstream install. I would highly recommend that you get a copy of TurnKey LAMP running in a VM and manually install the latest OTRS. Then use TKLBAM (or something else) to migrate your data and manually put it where it needs to go. There may be steps involved to upgrade your data to be compatible with your new OTRS install.