On 27 February 2020, the Chinese government introduced the 60 day extension rule.
Visas that expired before 28 February were automatically extended until 27 April 2020.
Visas issued before 27 February which expire after 27 February are automatically extended 60 days from the normal expiration date.
Visas issued after 27 February do not enjoy the automatic extension.
Some visas allow for more than one entry, but have a stay imit for each entry. As per some member experience who were not able to leave China within the allowed stay period and the stay period expired before 27 February, then their business visa automatically expired with the original stay period end, and then the 60 days extension applied bringing the actual expiration date to 27 April.
This rule applies to all types of visas with an expiration date. If the visa is a Business visa it is possible to obtain a 30 day business visa extension at the PSB providing all required document. See what happens when my 60-day automatic visa extension expires?