macOS 10.15 Catalina is not yet supported for use with Serato Pitch 'n Time Pro or LE.
We strongly recommend you do NOT upgrade to macOS 10.15 Catalina at this time.
We are currently working to ensure that these plugins are compatible with their officially supported DAWs.
Please note that Pitch 'n Time Pro & LE operating system support is dictated by the supported DAW that are you using, and its operating system support.
It may be worth disabling automatic updates, to avoid potentially clicking the "Install update" button in the macOS pop-up notification, via System Preferences --> App Store --> Automatically check for updates (uncheck).