This is a great feature if you use wall hosted families.If the family is a wall-hosted family, the Offset from Host parameter will move the family the specified distance from the wall since the wall is the host.

In 2020, The Schedule Level parameter has been moved up into the Constraints section.The Elevation parameter in 2019 was renamed to be Elevation from Level in 2020.The following illustration shows the same face-based family placed in a Revit 2019 project file and in a 2020 project file. Depending on the type of hosting of the element, when modifying one of these parameters, the other parameter may automatically change to the same value.Elevation from Level and Offset from Host parameters are new in Revit 2020.The Offset parameter in Revit 2019 no longer exists.The following illustration shows the same non-hosted cabinet family placed in a Revit 2019 project file and in a 2020 project file. I am showing just a couple of different examples to illustrate the changes. The parameter changes will be a bit different depending on the type of hosting mechanism used with a family. While they may or may not have much impact on your particular usage of Revit, it is important information of which to be aware. These changes can come into play when using automation, such as Dynamo. In Revit 2020, there are some changes in the built-in parameters for families when they are placed in a project file. With each release of software, there seems to be little things that change, but are either not documented as a change or the documentation on being a change is buried and difficult to locate.

Revit library 2019