They say it's important to listen to the tone of voice, but in fact, court judgments are often about parsing and interpreting text closely.
Although it's true that due to the shortage of judges, many judicial assistants and even clerks are writing judgments, any judgment issued must be reviewed.
And it surely reflects the court's will regarding the case, so the court's perspective on the matter is easily discernible within the judgment.
In Old Tang's view, the idea to muddy the waters in this case couldn't be clearer. On one hand, the court probably thinks that detaining someone for ten days over such a trivial matter was obviously wrong, which is why the judgment was revoked.
On the other hand, even though you have ample reasons, the impact of these kinds of administrative cases must be considered, hence letting the public security organs reissue the punishment.