Can no longer login when upgrading from Ember 2.x -> 3.x using ember-simple-auth

As the title reads, I am having trouble logging into my application after upgrading from Ember 2.x to 3.x (specifically in this case, 2.18.2 to 3.12.1). I tried following this guide : https://github.com/simplabs/ember-simple-auth/blob/master/guides/upgrade-to-v3.md

But it didn't really make sense to me. I tried setting the authenticationRoute, routeAfterAuthentication, and routeIfAlreadyAuthenticated values respectively to the particular routes that my application uses, and as I step through code execution with breakpoints I see that the values are being correctly set, but no dice. None of the other steps there applied to my particular case.

Here are the changes I've made based on the guide --

protected.js (all I did here was add the authenticationRoute definition) :

import { inject as service } from '@ember/service';
import { isNone } from '@ember/utils';
import AuthenticatedRouteMixin from 'ember-simple-auth/mixins/authenticated-route-mixin';
import AutoScrollMixin from 'erm/mixins/auto-scroll';

export default Route.extend(AuthenticatedRouteMixin, AutoScrollMixin, {
  authenticationRoute: 'login',
  session: service(),
  userIdle: service(),
  currentUser: service(),

  model(/*params, transition*/){
    var self = this;

    self.get('userIdle').on('idleChanged', (isIdle) => {
      if (isIdle) {
        self.get('session').invalidate();
        self.replaceWith('login');
      }
    });

    if( this.get('session.isAuthenticated') ) {
      var user = self.get('currentUser.user');
      if( user && user.get('temp_password') ) {
        this.transitionTo('change-password');
      }
    } else {
      if( isNone(this.get('session.isAuthenticated')) ||
          this.get('session.isAuthenticated') !== true ) {
        self.replaceWith('login');
      }
    }
  },
});

application.js (just added the routeAfterAuthentication entry) :

import { inject as service } from '@ember/service';
import { isNone } from '@ember/utils';
import ApplicationRouteMixin from 'ember-simple-auth/mixins/application-route-mixin';

export default Route.extend(ApplicationRouteMixin, {
  routeAfterAuthentication: 'risks.index',
  currentUser: service(),
  session:  service(),
  beforeModel() {
    return this._loadCurrentUser();
  },

  sessionAuthenticated() {
    this._super(...arguments);
    this._loadCurrentUser();
  },

  _loadCurrentUser() {
    var currUser = this.currentUser;
    return isNone(currUser.get('user')) ? currUser.load() : currUser.reload();
  }
});

login.js (all I did here was add the routeIfAlreadyAuthenticated entry) :

import UnauthenticatedRouteMixin  from 'ember-simple-auth/mixins/unauthenticated-route-mixin';

export default Route.extend(UnauthenticatedRouteMixin, {
  routeIfAlreadyAuthenticated: 'risks.index'
});