Hi! We build a Matter bridge that exposes air conditioners as compound devices, following Device Library §2.5.6 "Separate Endpoints": Aggregator → Bridged Node (no application device type) → Thermostat (0x0301) + Fan (0x002B) In the Home app some of these accessories appear as a Thermostat tile and others as a Fan tile, even when the devices are identical. A matter.js test bridge with 5 identical devices gave 1 Thermostat / 4 Fan tiles on Matter 1.5.1 and the same on 1.6.0. Removing and re-adding our ESP32 bridge, with no firmware change, swapped which device was shown as a Fan. Putting the Thermostat device type on the Bridged Node endpoint itself, with the Fan as its child, gave 3 Thermostat / 2 Fan, so that is not stable either (and Device Library 1.5 §2.5.6 does not allow it). The home hub log (homed, hmmtr.protocolmap) shows "Multiple primary service candidates found" for each of these devices; the chosen service is redacted. Questions: How does Home choose the primary service for a bridged compound device? Is there a supported way for the accessory to indicate which endpoint is primary (order in PartsList, TagList, something else)? Is a single endpoint with Thermostat plus an extra Fan Control server cluster the recommended layout for Apple Home instead? Filed as FB25263651. Environment: iPhone with iOS 27.0.1, Apple TV home hub with tvOS 27.0.

Hi, Selecting Auto mode in the Home app on a Matter Room AC device results in Cool being sent over Matter. Off, Heat and Cool work correctly. The reverse also fails: selecting Auto from another ecosystem (e.g. Samsung SmartThings) goes out correctly over Matter, but the Home app shows Cool. The issue is specific to the Room AC device type — with the same device exposed as Thermostat, everything works. In the logs, the Home app parses the requested mode correctly and sends it to the home hub; on the hub side the logs show Cool going out over Matter. Filed as FB25164477 (logs and repro attached). Is this a known issue? Thanks!