No se puede evitar que la partición APFS se monte automáticamente en Mojave (10.14.5)

Estoy tratando de evitar que MacOS me pida la contraseña de FileVault para 2 particiones APFS en el arranque. No quiero que se monten en absoluto.

Contenedor APFS:

/dev/disk1 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +121.1 GB   disk1
                                 Physical Store disk0s2
   1:                APFS Volume macOS                   43.2 GB    disk1s1
   2:                APFS Volume Preboot                 121.3 MB   disk1s2
   3:                APFS Volume Recovery                1.0 GB     disk1s3
   4:                APFS Volume VM                      1.1 GB     disk1s4
   5:                APFS Volume Shared                  7.7 GB     disk1s5
   6:                APFS Volume macOS Beta - Data       21.7 GB    disk1s6
   7:                APFS Volume macOS Beta              10.0 GB    disk1s7

Partición 1:

   Device Identifier:         disk1s6
   Device Node:               /dev/disk1s6
   Whole:                     No
   Part of Whole:             disk1

   Volume Name:               macOS Beta - Data
   Mounted:                   No

   Partition Type:            41504653-0000-11AA-AA11-00306543ECAC
   File System Personality:   APFS
   Type (Bundle):             apfs
   Name (User Visible):       APFS
   Owners:                    Disabled

   OS Can Be Installed:       No
   Booter Disk:               disk1s2
   Recovery Disk:             disk1s3
   Media Type:                Generic
   Protocol:                  PCI
   SMART Status:              Verified
   Volume UUID:               C6C28412-1505-4F19-8056-369FAE57B0CF
   Disk / Partition UUID:     C6C28412-1505-4F19-8056-369FAE57B0CF

   Disk Size:                 121.1 GB (121123069952 Bytes) (exactly 236568496 512-Byte-Units)
   Device Block Size:         4096 Bytes

   Volume Total Space:        0 B (0 Bytes) (exactly 0 512-Byte-Units)
   Volume Free Space:         0 B (0 Bytes) (exactly 0 512-Byte-Units)

   Read-Only Media:           No
   Read-Only Volume:          Not applicable (not mounted)

   Device Location:           Internal
   Removable Media:           Fixed

   Solid State:               Yes
   Hardware AES Support:      No

La segunda parte:

   Device Identifier:         disk1s7
   Device Node:               /dev/disk1s7
   Whole:                     No
   Part of Whole:             disk1

   Volume Name:               macOS Beta
   Mounted:                   No

   Partition Type:            41504653-0000-11AA-AA11-00306543ECAC
   File System Personality:   APFS
   Type (Bundle):             apfs
   Name (User Visible):       APFS
   Owners:                    Disabled

   OS Can Be Installed:       No
   Booter Disk:               disk1s2
   Recovery Disk:             disk1s3
   Media Type:                Generic
   Protocol:                  PCI
   SMART Status:              Verified
   Volume UUID:               55930D94-2CF3-481B-B845-FEAB3C492F23
   Disk / Partition UUID:     55930D94-2CF3-481B-B845-FEAB3C492F23

   Disk Size:                 121.1 GB (121123069952 Bytes) (exactly 236568496 512-Byte-Units)
   Device Block Size:         4096 Bytes

   Volume Total Space:        0 B (0 Bytes) (exactly 0 512-Byte-Units)
   Volume Free Space:         0 B (0 Bytes) (exactly 0 512-Byte-Units)

   Read-Only Media:           No
   Read-Only Volume:          Not applicable (not mounted)

   Device Location:           Internal
   Removable Media:           Fixed

   Solid State:               Yes
   Hardware AES Support:      No

Actual /etc/fstab que no funciona:

UUID=55930D94-2CF3-481B-B845-FEAB3C492F23 none apfs rw,noauto
UUID=C6C28412-1505-4F19-8056-369FAE57B0CF none apfs rw,noauto

¿Qué estoy haciendo mal? ¿Es por un error que he cometido o es /etc/fstab ¿ya no es compatible? ¿Qué es lo que /etc/fstab.hd ¿Para qué?

Sistema operativo: MacOS Mojave 10.14.5
Hardware: Macbook Air (13 pulgadas, principios de 2015)