hello and welcome to the forum,
have you tried running v1.56.0 on the upgraded setup, does it crash?
most likely,the machine is running out of memory due to the use of --check-first
"This means that all the info on the objects to transfer is held in memory before the transfers start."
--cache-db-purge --cache-chunk-no-memory
those is for the deprecated cache remote, and based on your config, that is not being used
is there a reason you are using --check-first --delete-before