What is difference between final episodes of training and test in DQN?

Question

What is difference between running in final episode of training mode and running in test mode in DQN?

Is there any difference more than after training and tune the hyper-parameters, we test for one episode and without any exploration? This means that test mode is similar to training mode in episode n+1 without exploring (while we train for n episode) ?Is it correct?

Why in some test code of DQN, they test for multiple episodes?