In the reports of COVID-19 pandemic situation, China's media often make special mention of 新疆生产建设兵团 after the provinces,autonomous regions and municipalities under the direct administration of central government.
What is the difference of 新疆 and 新疆生产建设兵团？Is it like the State of Washington and Washington District of Columbia, or New York City and New York State?
In the history, Xinjiang was firstly ruled by China in Han dynasty about 2000 years ago, which was even earlier than Tibet, Manchuria and Mongolia. The main purpose of controlling it is squeezing the living space of nomads in the North and maintaining trade routes with Central Asia (the Silk Road).
Because of the poverty of Xinjiang and long distance from the central plains, the rule in Xinjiang inflicted incredibly-steep costs on central governments of different dynasties. Any event (civil strife in the Central Plains, the invasion of Northern Nomads, local rebellion in Xinjiang, and etc.) will cause that central government lose control of Xinjiang. In fact, the central government had no effective jurisdiction over Xinjiang for more than half of the 2000 years.
In this background, most governments pursued a policy named 屯垦制 in the history. This policy allows garrisons to carry out production activities in peacetime. It improves local supply capacity and enlarges influence of central government. Although it abandoned professionalization of the army, it tied Xinjiang to central plains of China with lower cost in belif.
In the 1950s, after the establish of PRC, Chinese government decided to follow this ancient policy. And this is the origin of 新疆生产建设兵团.
But today, it is hard to make a simple defination on it.
It is a new concept in geograph. You can use 新疆生产建设兵团 as your address. Every unit with an official designation in 新疆生产建设兵团 has its own station, which covers an area of 70600 km² in total.
It can be considered as a state-owned company. Every product from 新疆生产建设兵团 will be printed with "produced by 新疆生产建设兵团".
It also can be regarded as a local government. After 70 years of development, there are more than three million people guided by 新疆生产建设兵团 directly.
As for its significance in military, I think 新疆生产建设兵团 has lost it in some extent. Since the improvement of Sino-Soviet relations in the 1980s, the independence of 新疆生产建设兵团 has been reduced by China's Ministry of National Defence. And Chinese govenment established Western Military Region to replace it formally in 2016.
Emm... I think you might get more confusion in it when you read here, right?
In the case that you mentioned in your statement, you can just understand 新疆生产建设兵团 as a geographical term. A special province beyonds the other normal provinces, autonomous regions and municipalities.
Nominally, the government of 新疆生产建设兵团 response to both Autonomous Region Government of Xinjiang and Central Government. In fact, it can be regarded as an province government directly under the jurisdiction of the central government in Xinjiang.
Make an example. There is a family with 3 members. Central government is daddy. Government of Xinjiang Autonomous Region（新疆自治区政府）and 新疆生产建设兵团 are sons. 新疆自治区政府 is the elder one and 新疆生产建设兵团 is the younger one. In the daily life, 新疆生产建设兵团 ask elder brother (新疆自治区政府) for help. But when there are some events, 新疆生产建设兵团 will return to central government directly.
And now, big event is coming (COVID-19). 新疆生产建设兵团 reports to central government directly instead of reporting to 新疆自治区政府 firstly. So the report from 新疆自治区政府 does not contain 新疆生产建设兵团, and China's media need to make special mention of 新疆生产建设兵团 after the provinces,autonomous regions and municipalities under the direct administration of central government.
It looks like @whx has put up a fairly detailed answer already, I'm just posting the info from Wikipedia as requested by OP:
Xinjiang Production and Construction Corps
The Xinjiang Production and Construction Corps (Chinese: 新疆生产建设兵团; pinyin: Xīnjiāng Shēngchǎn Jiànshè Bīngtuán), also known as XPCC or Bingtuan ("The Corps"), is a unique state-owned economic and paramilitary organization in the Xinjiang Uyghur Autonomous Region (XUAR) of China. The XPCC has administrative authority over several medium-sized cities as well as settlements and farms in Xinjiang. It has its own administrative structure, fulfilling governmental functions such as healthcare, policing, judiciary, and education for areas under its jurisdiction. Nominally subject to the XUAR, its internal affairs, including the administration of its cities and reclaimed land, is separate from that of the Autonomous Region and under direct control of the central government. The XPCC has been described to operate as a state within a state.
There is additional info on the page if you wish to read further.
Short answer, you may say there are two province units exist in one province, they manage their own business and they are on same level.
Not like the relations between New York City and New York State.
By the way, I was born in "Xinjiang Production and Construction Corps".
The difference between 新疆 and 新疆生产建设兵团 (Xinjiang Production and Construction Corps) is the same as the difference between "New York" and "New York One World Trade Center"
One World Trade Center is a building in New York
新疆生产建设兵团 is a production and construction group in Xinjiang
In Toronto, we only call our highest building "CN Tower", but people outside of Toronto might refer it as "Toronto CN Tower"
It is the only 屯垦兵团 in China now.
It is a mix of a party committee of 新疆, an administration of local government(the autonomous regions), a military unit(兵团), a company(中国新建集团公司).
The leader of the 新疆生产建设兵团(the first secretary of the 兵团's party committee) is also the leader of the autonomous regions(the secretary of autonomous region's party committee).
Under the leadership, there is a manager (it is also a company) who is also the commander of the 兵团.
