Unexpected 404 between example.com and www.example.com

#1
I have set up 301 redirects from example.com to www.example.com

Only on the www.example.com vhost I have set up a route to handle traffic and reverse-proxy it to a nodejs app running locally on a certain port.
For some very odd reason, the exact same setup works on a sub-domain e.g. staging.example.com and didn't on www.example.com - I text-diff compared both the configs and found no issues, restarted the lsws service several times to make sure my config had actually loaded.

Example of what was expected to work but was not working: https://www.example.com/proxied-route (returned 404)
Example of what was working with the exact same config on a different sub-domain/vhost: https://staging.example.com/proxied-route (got the proxied result -- so it worked)

What eventually made it ( https://www.example.com/proxied-route ) work was adding the same reverse-proxy config on example.com (non-www). I am left surprised as to why a different vhost example.com, would affect www.example.com

Is this a bug? Let me know if you want me to test something.

Running OpenLiteSpeed 1.8.1
 
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