PUBG mobile is showing a notification on April 3 that the servers of PUBG Mobile will be temporarily stopped for a whole day from 0:00 on April 4. Here they didn't give the explanation that why servers are going offline but made a statement that game will not work on April 4.
Tencent Games posted the reason on their official account on Weibo , In that post they explain that the company has taken this decision to honor and offer condolences to those who have martyred in the fight against the COVID-19.
These are exact words that are translated in English from Chinese:- "To express deep condolences to the martyrs and compatriots who died in the fight against New Crown Pneumonia, Tencent Games will be suspended for one day from 0:00 April 4 thin , including mainland China and Hong Kong,Macao and Taiwan regions .May the dead rest in peace, may the living work hard , and may the motherland flourish."
China is going to observe a National Mourning Day on April 4 for the victims of COVID-19, and for that reason Tencent Suspend PUBG Mobile servers for one day in various regions. (note:- India is not included in that list ,PUBG Mobile is running fine in India without any issue however Game notify that server will go down on April 4).
In China all embassies and public recreational facilities will be also be suspended to honor the victims of Coronavirus.