Automatic updates not working

[frnic]

Some time ago prior to Mojave I was able to simply click the update now button and go get a cup of coffee and when I came back the update would be done. 

Now, I have to disconnect all drives except the boot disk Mojave is installed on, and then at reboot I have to select the "Installer" on the Preboot volume a couple times until the final stage of the update is on the MacOS volume. Then it will finish okay and I can reconnect all my other drives.

Is this "normal" now, or do I have something not setup correctly? It isn't hard, just annoying.

TIA,

 

Frank