iOS 11.3 compatibility issue with AR Kit?

I keep getting this error when I try to launch my AR Project on an iPhone X, even though the project worked fine just 2 days ago. Same error appears with a blank AR Project.

LogPlayLevel: ERROR: Command failed (Result:5): /Users/Shared/Epic Games/UE_4.19/Engine/Binaries/DotNET/UnrealBuildTool.exe MyProject IOS Development -Project="/Users/name/Documents/Unreal Projects/MyProject/MyProject.uproject" “/Users/name/Documents/Unreal Projects/MyProject/MyProject.uproject” -NoUBTMakefiles -remoteini="/Users/name/Documents/Unreal Projects/MyProject" -skipdeploy -ini:Game:[/Script/UnrealEd.ProjectPackagingSettings]:BlueprintNativizationMethod=Disabled -noxge -nocreatestub -NoHotReload -ignorejunk. See logfile for details: ‘UnrealBuildTool-2018.04.10-08.40.04.txt’

Anybody else getting this problem? What am I doing wrong?

I have the same problem