Find out where in Nanchang is Public Security Bureau, and ask info about Visa extension there.

Go to any Bank in the city, and find English speaking Chinese at the Bank. If you have an account at any of Chinese Banks, ask them for address and directions to PSB. They will be glad to help you.

According from my files, the information I have will be pasted below, but I can not guarantee it will be up to date.  But try the telephones first, and confirm address.

I am not sure if you seek an extension on your "stay",  or what.  If so, cost will depend on nationality, and requirements will be at least a few days prior to expire, your passport, a few ID photos in case they are requested, the registration of address for visitors issued by local Police if not staying at a hotel, and must prove solvency by either showing cash or a local bank booklet with at least 20,000 to 30,000 yuan .

Visa extensions are granted for 30 days maximum, and you can get a total of two per stay.

Addresses are :

Jiangxi Province (Nanchang)

Police Office, Visa Extension and Lost Passports

Exit and Entry Management Section, Public Security Bureau

Nanchang

Address: No 1866 Feng Huang Zhong Avenue, Hong Gu Tan Xin Qu, Nanchang / ・s??・J??・V・・??・€・・・・・ｹ1866・・

Hour: Mon-Fri 9:00-12:00 and 1:30-5:00

Contact: 0791-8892 382 Miss Hu

Exit-Entry Administration Department of Nanchang Municipal Public Security Bureau / ????????????????????????

162, Lushan Nan Dadao, Nanchang City, Jiangxi Province /????????????????162・・

0971-8829388

(Mon-Fri) 8:30-12:00, 14:00-17:00

The Department of Public Security of Jiangxi Province

Address: No.133 Yangming Road , Nanchang City , Jiangxi Province

Tel: 0791-7288888

The Division of Entry-Exit Administration of the Department of Public Security of Jiangxi Province

Address: No.133 Yangming Road , Nanchang City , Jiangxi Province

Tel: 0791-7288490

Thanks for the info., I do appreciate it.