Whether this was due to a malicious complaint and subsequent retaliation... I'm not sure about the specific circumstances, so I won't offer an opinion.
However, based on my limited understanding, if a government agency wants to modify administrative approval procedures, should they issue a notification in advance? I haven't seen anyone else do this, so it probably doesn't happen.
I checked the official website of the Zhejiang Provincial Department of Economy and Information Technology and found only one document:
"Notification from the Zhejiang Provincial Economic and Information Technology Committee Regarding the Issuance of the "Zhejiang Province Amateur Radio Frequency Use Management Regulations""
Publication date: 2014-01-07
Effectiveness: Effective
Reference document number: Zhejiang Province Administration for Industry and Commerce, No. [2014]11
Standard document unified number: ZJSP03-2014-0002
Appendix: The "Zhejiang Province Amateur Radio Frequency and Bandwidth Allocation Table" clearly states that the 50.000-54.000 MHz band can be used.

