SCMP is itself source refer to a third party source. Caixin had a deleted report with about the same message. A few other apparently refer to the same blurry pics with a document saying something about SARS that were going around in Wechat groups in first week of January.

The first "something is going on" signal I remember was an article on aboluowang in the last week of December, where they cite a report of major mobilisation in provincial governments, and preparation for "medical emergency" starting first days of December.