Does anyone know if PG 12 can split the default partition into new partitions yet ? Currently, we have to manually detach the default partition, create the new

Does anyone know if PG 12 can split the default partition into new partitions yet ? Currently, we have to manually detach the default partition, create the new partitions, move the data from default partition to the newly created partitions, then re-attach the default partition. That's a lot of works compared to the reorganize partition feature of MySQL.