Táiwǎng liánbō, literally 'station and web broadcast together', is a drama sold to a television channel and a streaming platform at once, so that it airs on both under one schedule. The channel's run is fixed in advance and the streamer usually keeps its member schedule close to the channel's pace rather than running far ahead. The arrangement brings a national television audience, and with it the channel's calendar. Where the Mask Ends airs this way on CCTV-8 and Youku, which is why Youku's one-episode-a-day week followed the channel's slowdown.
Where it comes up

Where the Mask Ends vs Tigers Sniff the Rose: How One Hashtag Built a Duel the Calendars Don't Show
A Weibo hashtag read Youku's one-a-day calendar for Where the Mask Ends as a duel with Tencent's Tigers Sniff the Rose. The calendars, CCTV-8's own listings and the comment sections show a premium tier losing its lead over the TV channel, and two earlier disputes over release pace show the grievance is older than either show.