Ember 3.4 Scheduler Issue

controllers.application.js

import Ember from 'ember';
import { later, debounce } from '@ember/runloop';

export default Ember.Controller.extend({
  sync(schedulerType) {
    console.log("syncing via", schedulerType);
  },
  
  actions: {
  	case1() {
      console.log("Case 1");
    	debounce(this, this.sync, "debounce", 1000);
      later(this, this.sync, "later", 5000);
      setTimeout(console.log, 5000, "Case 1 complete");
    },
    
  	case2() {
      console.log("Case 2");
      later(this, this.sync, "later", 5000);
    	debounce(this, this.sync, "debounce", 1000);
      setTimeout(console.log, 5000, "Case 2 complete");
    },
    
  	case3() {
      console.log("Case 3");
      later(this, (arg) => this.sync(arg), "later", 5000);
    	debounce(this, this.sync, "debounce", 1000);
      setTimeout(console.log, 5000, "Case 3 complete");
    },
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<button {{action 'case1'}}>Case 1</button>
<button {{action 'case2'}}>Case 2</button>
<button {{action 'case3'}}>Case 3</button>

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.4.3",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2"
  }
}