How to use an In-Process AppService in a Multi-Instance UWP app

I am using an in-process AppService and want to support multi-instance in my UWP application. An in-process AppService must not have a value for its EntryPoint as the OnBackgroundActivated is used as EntryPoint. But when I set the SupportsMultipleInstances to true in the manifest, an EntryPoint for my AppService is being requested and it gives an error.

I have tried setting the EntryPoint of the AppService same as the EntryPoint of the Application in the manifest. This does make the error go away and I am able to run the app but the AppService connection is never established giving a status of AppUnavailable.

<Application Id="App" Executable="$targetnametoken$.exe" EntryPoint="UWP.App" desktop4:SupportsMultipleInstances="true">
      <Extensions>
        <uap:Extension Category="windows.appService" EntryPoint="UWP.App">
          <uap:AppService Name="SampleService"  />
        </uap:Extension>
      </Extensions>
</Application>

Here is the error message when I leave out the EntryPoint of the AppService.

DEP0700: Registration of the app failed. [0x80073CF6] AppxManifest.xml(32,10): error 0x80080204: Cannot register the package because EntryPoint must be specified when SupportsMultipleInstances is true.