Hi JRR
I've done a full test of this today - set up the config as expected for deep sea to remain always open, then loaded current version of the plugin
I did have to force the opening of deepsea by running /deepsea open as the deepsea manager wasn't running, as i generally keep it permanently disabled.
After a server save and restart, the deep sea is still running as expected.
troubleshooting
try opening it with /deepsea open and see what the console says. If it says 'Missing DeepSeaManager - creating' then good, give that 2-3 minutes. You might then need to run /deepsea open again
/deepsea status will tell you what's going on . If Busy = True, usually means opening is in progress. If you still don't see it opening after 10 mins, try /deepsea forceopen
Also worth checking if nothing else forces deepsea to be disabled (could be set in a hosts startup panel, or in server config file. Write deepsea.enabled in console to check, should be True)
My test config attached .
DeepSeaOptions.json