China's People's Liberation Army has sharply increased military activity in the airspace and waters east of Taiwan since mid-2025, deploying fighters, bombers, electronic warfare aircraft, and drones on multiple occasions in September to conduct surveillance of the island's eastern military infrastructure — a shift away from operations concentrated mainly in the Taiwan Strait to the west. Taiwan's Ministry of National Defense recorded PLA incursions into eastern airspace on at least eight days in September alone, with growing use of unmanned aerial vehicles suited for long-duration reconnaissance of key assets such as the Hualien and Taitung air bases and potential external reinforcement corridors. In response, Taiwan has begun treating its eastern flank as a frontline rather than a protected rear, deploying missile units to Orchid Island (a small island roughly 60 kilometres off Taiwan's southeastern coast, situated near the Philippines' Batanes Islands) and conducting blockade-breaking drills, moves that analysts say could anchor a broader First Island Chain defensive network involving Japan's southwestern islands and potentially the Philippines.