@BenzyNeez It looks like this is now a known and as yet (Beta 8) unresolved issue (thanks if you raised it!):
I wanted to mention that I have also seen inconsistencies in iPad testing against the iPad Pro 11-inch simulator which sounded somewhat similar to your experience and I'm hoping have the same underlying cause. In my case on first load the top inset has been reduced unexpectedly and my toolbar title is in the safe area (compared with >18.3). But when I go back to the iPad home screen and then return to the app it magically fixes itself and the top safe area inset is being respected again. Mentioning here in case others come looking. I'll raise a new report if this doesn't get resolved when the above is fixed.