The poster of that PTT article is also a doctor. Medical providers in Taiwan have heard about the rumor of SARS reappeared in China throughout December 2019. That doctor went looking for info on Chinese and Hong Kong social media sites. She was fortunate enough to grab the information before CCP scrubbed them from the internet. After Taiwan sounded the alarm, WHO told China. CCP started to crackdown nationwide. On 1/3 2020, CCP even told all the hospitals to turn over any samples that they have and anyone who leak information will be jailed.