Sync of sources notes and media seems not right

Is this a bug or a feature, does anyone know?

When using the Tree Share with Ancestry function sources, notes and media do not copy across for existing events. If you add it as a new item they do, but not for updating an event.
You can do the compare and it might say 3 sources on Ancestry and 1 in RM and you copy over the fact info, source etc. The fact info will copy and become blue but going back in shows that there are still 1 and 3 sources on either side of the record.

It also does not seem to correctly match up / compare source records even when they have the same details.

This shows a single source which looks identical on both sides but the source is flagged as red on both records.

Am I doing something wrong? I’m new to RM