cross-env APP_ENV=production expo r -c throws Invalid project root error after upgrade to Expo 45

After upgrading from Expo v44 to v45, starting my app in production env with the following npm run start-prod throws an error Invalid project root: /Users/user/code/username/projectname/r.

It seems like it is adding /r to my project root for no reason.

I am using a Managed Workflow with Expo.

package.json

"main": "node_modules/expo/AppEntry.js",
  "scripts": {
    "start-prod": "cross-env APP_ENV=production expo r -c",
  },
  "dependencies": {
    "expo": "^45.0.0",
    "react-native": "0.68.2",
    "cross-env": "^7.0.3",
...