New Twiddle

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  

});

controllers.my-route.js

import Ember from 'ember';

export default Ember.Controller.extend({
  queryA: '',
  queryB: '',
  
  queryParmas: ['queryA', 'queryB'],
  
  actions: {
    setQuery: function (query, value) {
    	this.set(query, value);  
    }
  }
});

controllers.my-route.sub-route.js

import Ember from 'ember';

export default Ember.Controller.extend({

});

router.js

import Ember from 'ember';
import config from './config/environment';

const Router = Ember.Router.extend({
  location: 'none',
  rootURL: config.rootURL
});

Router.map(function() {
  this.route('my-route', { path: '/:id' }, function () {
  	this.route('sub-route');
  });
});

export default Router;

routes.application.js

import Ember from 'ember';

export default Ember.Route.extend({
  beforeModel: function () {
  	this.transitionTo('my-route.sub-route', 1);  
  }
});

routes.my-route.js

import Ember from 'ember';

export default Ember.Route.extend({
  queryParams: {
  	queryA: {
      as: 'query_a',
    	refreshModel: true  
    },
  	queryB: {
      as: 'query_b',
    	refreshModel: true  
    }
  }
});

routes.my-route.sub-route.js

import Ember from 'ember';

export default Ember.Route.extend({
  model: function () {
    let deferred = Ember.$.Deferred();
    setTimeout(() => deferred.resolve(), 1000);
  	return deferred.promise();  
  }
});

templates.application.hbs

<ul>
  <li>Click Set on QueryA -> after resolving model on sub-route, query gets set to 1</li>
  <li>Click Set on QueryB -> after resolving model on sub-route, query gets set to 2, but QueryA resets</li>
  <li></li>
  <li>Remove my-route/loading.hbs file</li>
  <li>Click Set on QueryA -> after resolving model on sub-route, param gets set to 1</li>
  <li>Click Set on QueryB -> after resolving model on sub-route, param gets set to 2, QueryA stays same</li>
</ul>
<br>
<br>
{{outlet}}
<br>
<br>

templates.my-route.hbs

QueryA: {{queryA}} | <button {{action 'setQuery' 'queryA' '1'}}>Set</button> <br />
QueryB: {{queryB}} | <button {{action 'setQuery' 'queryB' '2'}}>Set</button> <br />
<br />
{{outlet}}

templates.my-route.loading.hbs

Loding....

templates.my-route.sub-route.hbs

Sub route

twiddle.json

{
  "version": "0.12.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.12.0",
    "ember-template-compiler": "2.12.0",
    "ember-testing": "2.12.0"
  },
  "addons": {
    "ember-data": "2.12.1"
  }
}