The "ad break" feature it is trialling means users cannot scroll or swipe past adverts as usual.
https://www.bbc.com/news/articles/c877y6mxdp7o?utm_source=dlvr.it&utm_medium=blogger
https://www.bbc.com/news/articles/c877y6mxdp7o?utm_source=dlvr.it&utm_medium=blogger