According to a statement from Chinese Government on the Adjustment of Labor Day Holiday Arrangements in 2019, the Labor Day holiday in 2019 has been extended to 4 days, from May 1 to 4.
But April 28 and May 5, 2 Sundays, will be workdays.
The revised Holiday Arrangements for 2019 is available at http://www.zgqz.biz/Government-Notices/19nianjiejiari.shtml
Source
http://english.gov.cn/policies/latest_releases/2019/03/22/content_281476573885344.htm
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