Comment on Why I prefer PSCONFIGUI.EXE over PSCONFIG.EXE by Alex Lknr

If PSConfigUI doesn’t want to show you upgrade screen that means all major upgrade steps have been done and you can just invoke failed step from PSConfig.
You can change value of SetupType key to B2B_UPGRADE value from below path:
HKLM:\Software\Microsoft\Shared Tools\Web Server Extensions\.0\WSS
This will force upgrade in PSConfigUI, but I advise not to do it manually.