P110(AU) TPAP lv2 authentication fails - isSameRegion: false (ap-southeast-1)

**Device Details** Model: P110(AU) Hardware Version: 1.0 Firmware Version: 1.4.0 Build 251020 Rel.161559 Encrypt Type: TPAP lv2 HTTP Port: 80 **Environment** Home Assistant Version: 2026.5.1 Integration Version: 3.5.0 HA running in Docker on Oracle Cloud (Ubuntu) Device accessed via Tailscale subnet router (GL.iNet) **Problem** Adding the device via the UI fails with: ERROR [DeviceFactory] None of available protocol is working, maybe invalid credentials ERROR [custom_components.tapo.config_flow] Failed to setup, invalid auth plugp100.errors.invalid_authentication.InvalidAuthentication: Invalid authentication error for 192.168.8.231, None Credentials are confirmed correct — login works via tplinkcloud.com and the Tapo app. Root Cause (suspected) When querying the TP-Link cloud API the device list returns isSameRegion: false with deviceRegion: ap-southeast-1. The integration appears to be authenticating against the wrong regional endpoint, causing auth failure despite valid credentials. Cloud API confirms the account region is ap-southeast-1 and the correct server is https://aps1-wap.tplinkcloud.com. The tapo Python library (mihai-dinculescu, v0.9.0) also fails with: Unauthorized { kind: "FORBIDDEN", description: "Make sure Third-Party Compatibility is turned on in the Tapo app..." } Third-Party Compatibility is confirmed enabled. **Steps to Reproduce** Have a P110(AU) hw 1.0 with fw 1.4.0 registered to an Australian TP-Link account (region ap-southeast-1) Attempt to add device via Settings → Devices & Services → Add Integration → Tapo Enter device IP and valid Tapo credentials Auth fails as above **Expected Behaviour** Integration should authenticate successfully and add the device. **Additional Notes** Device is reachable on the network (ping and HTTP on port 80 both work). The device responds to HTTP POST on /app with error_code 1003 when sent a handshake with an empty key, confirming the SHIP 2.0 local API is active and reachable.