You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Doctor_Who

Context:
The serial format changed for the 2005 revival, with each series usually consisting of 13 45-minute, self-contained episodes (60 minutes with adverts, on overseas commercial channels), and an extended episode broadcast on Christmas Day. Each series includes several standalone and multi-part stories, linked with a loose story arc that resolves in the series finale. As in the early "classic" era, each episode, whether standalone or part of a larger story, has its own title. Occasionally, regular-series episodes will exceed the 45-minute run time; notably, the episodes "Journey's End" from 2008 and "The Eleventh Hour" from 2010 exceeded an hour in length.

Question:
When was an extended episode of Doctor Who shown?

Christmas Day