I'm also having the same issue. Software Updater was present after new update. When I closed the CCleaner and reopened CCleaner Software Updater no longer was available in tools tab. I then uninstalled and reinstalled a fresh version. Software Updated was present for the first initial run and once closed Software Updated was no longer available.
CCleaner Pro Plus: v5.55.7109 (64-bit)
OS: Windows 10 x64 1809