Does the 4-month free trial subscription end automatically?

Yes, the free trial period for your Spotlight add-on ends automatically. You do not need to cancel it. 

In addition: At the end of the free trial period, your Spotlight profile and your data transferred via Filmmakers will be automatically deleted at Spotlight , unless you actively decide to keep the Spotlight add-on.

You will receive an email from Filmmakers before the end of the trial period with the information that you can book the Spotlight add-on for a fee. The booking does not happen automatically, but only if you actively select it.