The secretary-general of the municipal government and the director of the municipal office are both at the level (if they are ordinary prefecture-level cities)
But the Secretary-General is in charge of the general direction. The director of the municipal office is actually a senior secretary, and the secretary-general is a senior consultant assistant.
So although it is horizontal, in fact, the rights are different. However, if the Deputy Secretary-General concurrently serves as the director of the Municipal Office, the level will be in the middle.