ESPHome separates the online status of MQTT-connected boards built from the same configuration. When a device’s name includes its hardware-address suffix, that suffix also identifies its default status and log messages; previously the boards shared those messages despite having distinct names.
A companion change waits briefly for the message broker to acknowledge a shutdown message before disconnecting. Tests on ESP32 and ESP8266 boards received the message on every tested restart, where the old code missed most of them. The wait remains bounded by the shutdown timeout.
Custom topics remain unchanged. After updating a setup that uses name suffixes, the old shared status topic retains its last offline message and may need clearing if anything still watches it.