A corporate spiritual stronghold is put in place by civic or religious (sometimes both) submitting to a powerful evil spirit in the past, so it has to be broken by the current corporate leaders. If the religious and civic leaders of Christchurch agreed to renounce the stronghold that is controlling their city it would lose its power.
However, this is unlikely to happen. The religious and civic leaders of Christchurch will find it difficult to agree. They would also have to commit to forgoing the use of manipulation, control and intimidation. Some leaders who have relied on these tools for a long time would find it hard to function without them. Fortunately, God had another way that he can defeat this stronghold.