This covers some of the more esoteric and time consuming glitches that may occur. Hopefully if you find the issue here, it will save you hours of debugging
sbt assembly might not be merging the required META-INF properly. See sanityCheck for clues and review the MergeStrategy carefully
If you are using a VPN, DNS entries can get messed up. sanityCheck may help save you on this. dscacheutil -flushcache might be a useful command
The quotes db loading or other "priming" before serving a request is taking a long time, causing web requests to get queued and then rejected
application.conf might have got accidentally committed with a change to source quotes from file system rather than the database
Apparently can be caused when certain uncaught exceptions happen. Exact root cause still unknown
Possibly same as previous