If "D" refers to a specific show like Derry Girls or Dark Money (both of which had active seasons/episodes around that time), searching for the of the show on these platforms will yield better results than using the technical filename.
: The primary hub for BBC content. You can check the BBC iPlayer to see if the series is currently available in their library. Download File D.2019.UK.S03E04.mp4
: For high-end UK dramas and Sky Original content, check the NOW TV or Sky Go platforms. If "D" refers to a specific show like