2. It is not necessarily civil servants who enter the tax bureau, and there are often temporary workers in the tax bureau.
3. Civil servants can also retire and resign.
4. So it's normal to be a CFO in another company.
5. It is a serious violation of law and discipline to be the chief financial officer of an on-the-job civil servant.
6. It is also possible for the state-owned enterprises mentioned above, but that kind of situation is done by higher-ranking civil servants. There is no problem in exchanging the two, and it has nothing to do with the small soldiers in the tax bureau.
Personal opinion, for reference only.