I have 2 stacks using Pulumi.Aws v4.5.1: a network stack and an application stack. The application stack has a stack reference to the network stack, but not a project referrence. The 2 stacks share no dependencies. I can upgrade the network stack to v4.30.0, but if I then try to upgrade the application stack it hangs. I can then revert the network stack back to 4.5.1 and pulumi up on the application stack is then OK. I can then try to upgrade the application stack and leave the network stack on v4.5.1. The result: pulumi up on the application stack hangs again.