Ubuntu loses display settings on reboot, corrupts displays

I have two displays, one on display port, and one on VGA. The display port display is a Seiki Pro 40" display in landscape at 3840x2160. The VGA is an HP 24" display in portrait at 1920x1200.

If I boot with either display by itself, everything works fine. If I plug in the other display and configure it to run multidisplay, everything is fine.

When I reboot, the display settings are changed from "Join Displays" to "Mirror", the 40" is set to 1920x1200 landscape (which it cannot actually do), and the 24" is set to 1920x1200 landscape. The 24" is also set to primary (whereas I selected the 40" as primary before rebooting.)

The 40" display is messed up with overdraw, etc. In addition, I can no longer select 3840x2160 for the 40". If I turn of the 40" and turn it on again, eventually the settings box will let me select 3840x2160. Once I select it, the screen flashes but does not come back to 3840x2160. (ie., it is still corrupted with overdraw and presumably running at 1920x1200.). If I toggle the display power several times, it will eventually come back running at the correct resolution.

ProblemType: Bug
DistroRelease: Ubuntu 18.10
Package: gnome-shell 3.30.2-0ubuntu1.18.10.1
ProcVersionSignature: Ubuntu 4.18.0-17.18-generic 4.18.20
Uname: Linux 4.18.0-17-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.10-0ubuntu13.2
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Tue Apr 16 10:58:08 2019
DisplayManager: gdm3
GsettingsChanges:
 b'org.gnome.shell' b'favorite-apps' redacted by apport
 b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'"
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/usr/bin/fish
SourcePackage: gnome-shell
UpgradeStatus: No upgrade log present (probably fresh install)
mtime.conffile..etc.logrotate.d.apport: 2019-01-12T15:50:59.090583