deffinately some sort of problem with the Database upgrade portion. Moved my settings over to the linuxserver.io container to test and can see the upgrade occur but then the same crashes after.
[cont-init.d] 10-adduser: exited 0.
[cont-init.d] 40-chown-files: executing...
[cont-init.d] 40-chown-files: exited 0.
[cont-init.d] 45-plex-claim: executing...
[cont-init.d] 45-plex-claim: exited 0.
[cont-init.d] 50-gid-video: executing...
[cont-init.d] 50-gid-video: exited 0.
[cont-init.d] 60-plex-update: executing...
Atempting to upgrade to: 1.19.1.2621-b249be3b0
2020-04-04 15:37:16 URL:https://downloads.plex.tv/plex-media-server-new/1.19.1.2621-b249be3b0/debian/plexmediaserver_1.19.1.2621-b249be3b0_amd64.deb [91119418/91119418] -> "/tmp/plexmediaserver_1.19.1.2621-b249be3b0_amd64.deb" [1]
(Reading database ... 10446 files and directories currently installed.)
Preparing to unpack .../plexmediaserver_1.19.1.2621-b249be3b0_amd64.deb ...
PlexMediaServer install: Pre-installation Validation.
PlexMediaServer install: Docker detected. Preinstallation validation not required.
Unpacking plexmediaserver (1.19.1.2621-b249be3b0) over (1.18.9.2578-513b381af) ...
Setting up plexmediaserver (1.19.1.2621-b249be3b0) ...
PlexMediaServer install: Docker detected. Postinstallation tasks not required. Continuing.
Processing triggers for libc-bin (2.27-3ubuntu1) ...
[cont-init.d] 60-plex-update: exited 0.
[cont-init.d] 99-custom-scripts: executing...
[custom-init] no custom files found exiting...
[cont-init.d] 99-custom-scripts: exited 0.
[cont-init.d] done.
[services.d] starting services
Starting Plex Media Server.
[services.d] done.
****** PLEX MEDIA SERVER CRASHED, CRASH REPORT WRITTEN: /config/Library/Application Support/Plex Media Server/Crash Reports/1.19.1.2621-b249be3b0/PLEX MEDIA SERVER/25fef65b-2e88-3706-424a2f9d-08e97f82.dmp
Starting Plex Media Server.
Error starting framework core for /usr/lib/plexmediaserver/Resources/Plug-ins-b249be3b0/PlexMusic.bundle.
****** PLEX MEDIA SERVER CRASHED, CRASH REPORT WRITTEN: /config/Library/Application Support/Plex Media Server/Crash Reports/1.19.1.2621-b249be3b0/PLEX MEDIA SERVER/4b063399-5431-8024-0ec2f67c-1e3d0ab0.dmp
Starting Plex Media Server.
****** PLEX MEDIA SERVER CRASHED, CRASH REPORT WRITTEN: /config/Library/Application Support/Plex Media Server/Crash Reports/1.19.1.2621-b249be3b0/PLEX MEDIA SERVER/1e27924b-fccb-9594-4478833a-6b75cabd.dmp
Starting Plex Media Server.
There are some rumblings on the plex forums about it but i doubt the vast majority of users will be running this new version so it may not get much traction until then.
Only thing i can think of doing (if they don't fix it) is to export my watch settings and start fresh.