For me: youtube-dl.exe -f bestvideo+bestaudio "https://vod-dash-ww-live.akamaized.net/usp/auth/vod/piff_abr..."
And the subtitle(EBU-TT-D format): https://vod-sub-ww-live.bbcfmt.s.llnwi.net/iplayer/subtitles...
Vlc can play it with the sub.