Mar 30 21:44:02.661572 LibreELEC kernel: usb 1-1: new high-speed USB device number 2 using ehci-pci
Mar 30 21:44:02.661646 LibreELEC kernel: usb 3-3: new high-speed USB device number 2 using xhci_hcd
Mar 30 21:44:02.661717 LibreELEC kernel: usb 2-1: new high-speed USB device number 2 using ehci-pci
Mar 30 21:44:02.661791 LibreELEC kernel: hub 1-1:1.0: USB hub found
Mar 30 21:44:02.661858 LibreELEC kernel: hub 1-1:1.0: 4 ports detected
Mar 30 21:44:02.661924 LibreELEC kernel: scsi host4: uas
Mar 30 21:44:02.662003 LibreELEC kernel: scsi 4:0:0:0: Direct-Access JMicron Disk0 0105 PQ: 0 ANSI: 6
Mar 30 21:44:02.662073 LibreELEC kernel: hub 2-1:1.0: USB hub found
Mar 30 21:44:02.662140 LibreELEC kernel: hub 2-1:1.0: 6 ports detected
Mar 30 21:44:02.662216 LibreELEC kernel: scsi 4:0:0:1: Direct-Access JMicron Disk1 0105 PQ: 0 ANSI: 6
Mar 30 21:44:02.662290 LibreELEC kernel: sd 4:0:0:0: Attached scsi generic sg0 type 0
Mar 30 21:44:02.662362 LibreELEC kernel: sd 4:0:0:1: Attached scsi generic sg1 type 0
Mar 30 21:44:02.662433 LibreELEC kernel: sd 4:0:0:0: [sda] 7814037168 512-byte logical blocks: (4.00 TB/3.64 TiB)
Mar 30 21:44:02.662504 LibreELEC kernel: sd 4:0:0:1: [sdb] 7814037168 512-byte logical blocks: (4.00 TB/3.64 TiB)
Mar 30 21:44:02.662574 LibreELEC kernel: sd 4:0:0:0: [sda] Write Protect is off
Mar 30 21:44:02.662644 LibreELEC kernel: sd 4:0:0:0: [sda] Mode Sense: 67 00 10 08
Mar 30 21:44:02.662713 LibreELEC kernel: sd 4:0:0:1: [sdb] Write Protect is off
Mar 30 21:44:02.662784 LibreELEC kernel: sd 4:0:0:1: [sdb] Mode Sense: 67 00 10 08
Mar 30 21:44:02.662854 LibreELEC kernel: sd 4:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports DPO and FUA
Mar 30 21:44:02.662924 LibreELEC kernel: sd 4:0:0:1: [sdb] Write cache: enabled, read cache: enabled, supports DPO and FUA
Mar 30 21:44:02.662998 LibreELEC kernel: sd 4:0:0:0: [sda] Preferred minimum I/O size 4096 bytes
Mar 30 21:44:02.663182 LibreELEC kernel: sd 4:0:0:0: [sda] Optimal transfer size 33553920 bytes not a multiple of preferred minimum block size (4096 bytes)
Mar 30 21:44:02.663255 LibreELEC kernel: sd 4:0:0:1: [sdb] Preferred minimum I/O size 4096 bytes
Mar 30 21:44:02.663325 LibreELEC kernel: sd 4:0:0:1: [sdb] Optimal transfer size 33553920 bytes not a multiple of preferred minimum block size (4096 bytes)
Mar 30 21:44:02.663334 LibreELEC kernel: Alternate GPT is invalid, using primary GPT.
Mar 30 21:44:02.663341 LibreELEC kernel: sda: sda1 sda2
Mar 30 21:44:02.663409 LibreELEC kernel: sd 4:0:0:0: [sda] Attached SCSI disk
Mar 30 21:44:02.663417 LibreELEC kernel: sdb: sdb1 sdb2
Mar 30 21:44:02.663485 LibreELEC kernel: sd 4:0:0:1: [sdb] Attached SCSI disk
Mar 30 21:44:02.663556 LibreELEC kernel: usb 3-5: new full-speed USB device number 3 using xhci_hcd
Mar 30 21:44:02.664086 LibreELEC kernel: usb 3-6: new high-speed USB device number 4 using xhci_hcd
Mar 30 21:44:02.664231 LibreELEC kernel: usb-storage 3-6:1.0: USB Mass Storage device detected
Mar 30 21:44:02.664297 LibreELEC kernel: scsi host5: usb-storage 3-6:1.0
Mar 30 21:44:02.664454 LibreELEC kernel: scsi 5:0:0:0: Direct-Access SanDisk Cruzer Blade 1.26 PQ: 0 ANSI: 5
Mar 30 21:44:02.664525 LibreELEC kernel: sd 5:0:0:0: Attached scsi generic sg2 type 0
Mar 30 21:44:02.664595 LibreELEC kernel: sd 5:0:0:0: [sdc] 31266816 512-byte logical blocks: (16.0 GB/14.9 GiB)
Mar 30 21:44:02.664664 LibreELEC kernel: sd 5:0:0:0: [sdc] Write Protect is off
Mar 30 21:44:02.664735 LibreELEC kernel: sd 5:0:0:0: [sdc] Mode Sense: 43 00 00 00
Mar 30 21:44:02.664805 LibreELEC kernel: sd 5:0:0:0: [sdc] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
Mar 30 21:44:02.664814 LibreELEC kernel: sdc: sdc1 sdc2
Mar 30 21:44:02.664882 LibreELEC kernel: sd 5:0:0:0: [sdc] Attached SCSI removable disk
Mar 30 21:44:02.664891 LibreELEC fsck: fsck.fat 4.2 (2021-01-31)
Mar 30 21:44:02.664900 LibreELEC fsck: /dev/sdc1: 12 files, 38232/65501 clusters
Mar 30 21:44:02.664907 LibreELEC fsck: Storage: clean, 5120/944704 files, 233249/3776128 blocks
Mar 30 21:44:02.664919 LibreELEC kernel: EXT4-fs (sdc2): mounted filesystem with ordered data mode. Quota mode: disabled.
Mar 30 21:44:04.083037 LibreELEC kernel: ntfs3: Max link count 4000
Mar 30 21:44:04.086573 LibreELEC kernel: ext3: Unknown parameter 'fmask'
Mar 30 21:44:04.086628 LibreELEC kernel: ext3: Unknown parameter 'fmask'
Mar 30 21:44:04.109703 LibreELEC kernel: ext2: Unknown parameter 'fmask'
Mar 30 21:44:04.109778 LibreELEC kernel: ext2: Unknown parameter 'fmask'
Mar 30 21:44:04.109802 LibreELEC kernel: ext4: Unknown parameter 'fmask'
Mar 30 21:44:04.109819 LibreELEC kernel: ext4: Unknown parameter 'fmask'
Mar 30 21:44:04.109839 LibreELEC kernel: squashfs: Unknown parameter 'fmask'
Mar 30 21:44:04.113106 LibreELEC kernel: squashfs: Unknown parameter 'fmask'
Mar 30 21:44:04.113141 LibreELEC kernel: F2FS-fs (sda2): Magic Mismatch, valid(0xf2f52010) - read(0x8e0e8966)
Mar 30 21:44:04.113157 LibreELEC kernel: F2FS-fs (sda2): Can't find valid F2FS filesystem in 1th superblock
Mar 30 21:44:04.119707 LibreELEC kernel: F2FS-fs (sda2): Magic Mismatch, valid(0xf2f52010) - read(0x0)
Mar 30 21:44:04.119759 LibreELEC kernel: F2FS-fs (sda2): Can't find valid F2FS filesystem in 2th superblock
Mar 30 21:44:04.119778 LibreELEC kernel: F2FS-fs (sdb2): Magic Mismatch, valid(0xf2f52010) - read(0x8e0e8966)
Mar 30 21:44:04.119793 LibreELEC kernel: F2FS-fs (sdb2): Can't find valid F2FS filesystem in 1th superblock
Mar 30 21:44:04.123273 LibreELEC kernel: F2FS-fs (sdb2): Magic Mismatch, valid(0xf2f52010) - read(0x0)
Mar 30 21:44:04.123330 LibreELEC kernel: F2FS-fs (sdb2): Can't find valid F2FS filesystem in 2th superblock
Mar 30 21:44:04.230206 LibreELEC udevil[814]: mount: mounting /dev/sdb2 on /media/4TB failed: Invalid argument
Mar 30 21:44:04.230376 LibreELEC udevil[813]: mount: mounting /dev/sda2 on /media/NewVolume failed: Invalid argument
Mar 30 21:44:04.230440 LibreELEC udevil[710]: mount: mounting /dev/sda2 on /media/NewVolume failed: No such device
Mar 30 21:44:04.230549 LibreELEC udevil[711]: mount: mounting /dev/sdb2 on /media/4TB failed: No such device
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The update process will have absolutely zero impact. The completely different software stack that you're running post-update *can* have an impact (as we bumped ~95% of the packages in the distro; stuff has changed). The log shows both drives have issues mounting. It's unclear to me which filesystem is being used on the drives; there are messages about ext2/3/4, ntfs3 and f2fs.