Complex sentence: On 6 November 2015, TVB released its 2016 calendar, which has a promotional image of "A Fist Within Four Walls" attached to the month of November 2016.
Split into simpler sentences: On 6 November 2015, TVB released a promotional poster for "A Fist Within Four Walls" as an image for TVB's 2016 calendar. The image was attached to the month of November 2016.