Just an update post for the record that 
The witness node is currently hosted with Privex using the pre-replayed VPS located in Sweden, and I have been using it for over a year without issues until this got hit 2 days ago. For reference, the previous downtime was scheduled on 7 November 2021 when the disk had to be resized. It is the only other downtime with this provider.
The pre-replayed image was 3 weeks old hence it needs to catch up with the network, and unfortunately this is running slow as it replays at a rate of ~10b/s. As expected, this is due to disk I/O bottleneck as the VPS only has 8GB of RAM to work with. The CPU scored poorly on Geekbench 5 as well.
This remains an ongoing incident and will update here as the story develops.
In the worst case scenario (and probably long term as well), I may have to move this server off to a dedicated instance that might cost more, and likely spin up a backup hived node on a NUC that I bought for another blockchain. It might even help with the ridiculously high block time offsets that I often see on techcoderx.com node even with v1.26 optimizations.
Update 1 (19/8/2022 08:48 UTC): Caught up with the network, price feed is also now up to date.
Update 2 (19/8/2022 09:25 UTC): Subsequently a block has been produced successfully.
Update 3 (20/8/2022 04:47 UTC): It is now techcoderx.com's turn.
block_log file size (compressed): 323 GB
block_log.artifacts file size: 1.6 GB
shared_memory.bin file size: 20 GB
blockchain folder size: 345 GB
Output of SELECT pg_size_pretty( pg_database_size('block_log') );
Database size: 2,976 GB
Output of SELECT pg_size_pretty( pg_database_size('hive') );
Database size: 533 GB
Compressed: 206 GB
RAM usage: 4.5 GB
Compressed disk usage: 1.4 TB
