By two months I mean until the time the CCP made public announcement around Jan 2x, relative to the reported date of first patient 2019-12-01, which is supported by CCP's own media (for eg: http://www.bjnews.com.cn/news/2020/02/23/693805.html).

A little bit off topic: for me, this first case looks very impossible to be the first one, and it further supports my theory that wuhan virus is a bio-weapon created by CCP and got leaked. That is why it is so hard to pinpoint the zero patient because CCP is hiding this info.

The Virologists that host the TWIV podcast cited some studies suggesting that the first cases were likely in October or November, which went undetected.