We are finding that if you use one of the 2019 products it changes the database so the older version products don't function correctly anymore.  The "Setup", "sections", "Process" & "NESTING" files get updated which effect CAD, CAM & EST running older versions.  There are also estimate files that get updated.

I thought if I upgraded all employees to 2019 then the problem would be fixed.  But I found that when I went back to Revit 2017 for a project we were working on I could no longer add services to the Revit project.  The database was not able to read correctly so no additional services could be added.

It is known that when a project is in a specific version of Revit you need to stay in that version when possible and if you are using collaboration for Revit (which I am) you have no choice but to use the correct version of Revit that the project is on.  Is anyone else having a similar problem or know of a fix to allow older Revit Fabrication versions to use a newer database?  I am resistant to the idea of making a copy of the database just for the older versions of Revit but I don't know what else to do.