I’m actually running Ardour 5.5.0. I downloaded the 5.12 when it became available but since I was working on several tracks, I preferred to wait and upgrading the version later.
One thing I’d like to know: to do the upgrade I just need to install the lates version or do I have to remove the older first?
Is there any problem/issue with tracks made with a previous version?
Thanks
Ok I thought you meant downloading who knows from where. No, I always downloaded them from here. I mean the full version, I don’t remember if the version available to everybody gets silences every certain time.
What I mean is: many Linux users get ardour from their Linux distribution’s package management system. The story there is totally different. Thanks for your support. Also, you don’t have to subscribe to download any version.
@ StratoJ: thanks SJ, I think the first version ever I owned it’s the 5.5 or so, so I shouldn’t have any problem
@Paul: I don’t know what you mean with “install from ardour.org”. ALL the version I had/have were downloaded from here, since I contributed TWICE to financing Ardour, making a subscription and making a donation since, as usual, it wasn’t specified clearly that you have to subscribe first to download any version.
@telover: the only problems I have seen here is when open session from A3 or A2. It was something strange with aux. sends. And, since the distro used have been updated and the plugins installed are different, some missing plugins that Ardour5 replaced by an empty slot. Of course, open an old session like that is almost always for remix it, so it was not a real problem!!! 5.12 is nice you can go to it and will have zero problem with 5.X sessions 
Ardour 5.x loads all Ardour 5.x sessions, and more or less every older session too.
If you install from ardour.org, you can leave the existing version in place, if you wish to have “insurance”. You can always remove it later with the uninstall script that can be found inside the folder.
If you do not install from ardour.org, good luck! We don’t support 3rd party builds.