This time the mainland made a move, unilaterally announcing a decision, which directly erased the existence of the "middle line of the strait" and opened a breakthrough in the Taiwan Strait, what is the decision? And how did you open the breakthrough?
According to the Global Times, the Civil Aviation Administration of China announced that from February 1, it will cancel the flight bias of the M503 route from north to south, and will then re-enable two routes connected with the M503 route, namely the W122 and W123 routes from west to east, in order to improve the efficiency of aviation operations. 
It is worth mentioning that this is a decision unilaterally announced by the mainland, and no consultation has been made with the Taiwan authorities. As soon as this news came out, it immediately set off a thousand waves on Taiwan Island, touching the sensitive nerves of all parties on the island, especially ***
For example, Taiwan publicly expressed strong condemnation of the mainland's behavior, saying that if the mainland insists on going its own way and does not change its decision, it will inevitably bear a serious price.
In addition, some people have been clamoring that the mainland is undermining the harmony and stability in the Taiwan Strait and should immediately stop its misconduct, and some people claim that the mainland's move has undermined the status quo of the situation in the Taiwan Strait and should immediately start consultations with the island.
After reading the speeches made by people from all walks of life on the island, and in the face of their unequivocal condemnation, some people still think that the mainland has done something to them, not to mention that Taiwan belongs to China in the first place, and the mainland only needs to obey its decision-making opinions; in the past, they connived at Taiwan, and the Taiwan authorities have become closer to the United States, and some people on the island really regard themselves as outsiders? 
Chen Binhua, spokesman for the Taiwan Affairs Office of the State Council, responded directly, saying that the M503 route is only a civil route, and it is used to relieve aviation pressure and ensure aviation safety, and this is only the mainland's routine work in civil aviation management, and there is no need to negotiate with Taiwan. Then again, why is the island so excited?
This has to start from the 50s of the last century, when the Taiwan authorities signed an agreement with the United States, in which the United States demanded that Taiwan military fighters and warships must operate within the prescribed limits, and once the line was crossed, the United States would not be able to guarantee the security of the Taiwan military.
The mainland's move is actually quietly erasing the "middle line of the strait", because this line was blurred before, and now the M503 route has been canceled, and two routes connecting with it will be reactivated, so that the "middle line" can be crossed at any time in the future.
Proceeding from the "** elements' point of view, the mainland's current action has indeed caught them off guard, and in the future, the mainland's planes will be able to cross the "middle line" at any time, which will certainly deter the situation on the island. 
However, from the perspective of cross-strait reunification, this move will better connect the ties between the mainland and the Taiwan region, and the two sides have already had close contacts before, and the abolition of the "middle line" setting can further strengthen the implementation of sovereignty over Taiwan and open up a breakthrough in the Taiwan Strait, which is of very far-reaching significance.
If the mainland does not make a sound, it is just a blockbuster, which not only makes people unable to find fault and promotes friendly exchanges between the two sides of the strait, but also invisibly blows at the arrogance of the "leading forces." If the relevant forces on Taiwan continue to be obsessed with it, then there will be many more times for the mainland to "make its own claims" in the future.