TLDR; I have created a Home Assistant (HA) custom component to support states that have occurred in the past. This integration sets a state’s
last_changed datetimes based on client data. You can find the project and more details at https://gitlab.com/jbeckman/retro_state.
Unfortunately there is no official support to handle historic states in HA. This seemed odd to me as many components in HA do not have true, real-time states. Any cloud component will incur some latency, which unreliable internet would magnify. The frequency of published reports limits batch processing to that instant (exhibit A). …