As the Winter Olympics and the Lunar New Year holiday loom, Mimi Lau looks at Beijing's desperate measures to maintain its zero-Covid policy amid new outbreaks in Tianjin and Henan province. Holly Chik unpacks the claim that Covid-19 is entering China by mail; Shanghai-based journalist Thomas Yau on what it's like to travel through China right now, and Bernice Chan details the massive changes to Hong Kong's famed restaurant industry amid a harsh 6pm lockdown policy. Get our Listening Post…