The freeway segments were downgraded to trunk roads in <https://www.openstreetmap.org/changeset/119016536>. It seems wrong for motorway_links to only lead to trunk roads. OTOH access to the Rockbank Nursery (& Caravan Pk further east) is directly from the freeway. Do any horse/tractor/etc restrictions apply to this section?

It looks like there used to be freeway crossings at e.g. Paynes Rd, but they all seem blocked off now with wire rope barriers. I believe the closest U turns would be Leakes Rd and Melton Hwy interchanges.