Steps to reproduce:

1. Create a course without any synchronizable attributes, fill mandatory fields and save it.
2. Add synchronizable attributes in your project (by adding an Apogée SCC on courses).
3. Edit the course, change nothing and save it.
   
4. Reopen it.
   
5. The value of the courseType ("nature") attribute has been changed to the alt one.

This kind of behavior can appears when adding a new SCC or after migrations that didn't force the local status, it's only done for previously synchronized attributes.

Technical analysis:
In the EditContentFunction, we make a call to ExternalizableMetadataHelper.updateStatus(), the default value when no status is defined is null instead of local, so current status is different than targetted status and current and alt values are inverted.

Note that new API seems to be OK.