iPhone Presence Sensor not working reliably

I’ve had repeated issues where my wife’s iphone is shown as away when it’s clearly in the house. This has resulted in a few false alarms with SHM, which compounded with the bug that prevented me dismissing it for 20 mins to make a bad SmartThings day.

If I look at the presence log for her phone, I can see repeatedly mismatched arrivals/departures (Where she departs twice for instance). These coincide with the false alarms. What causes this? Are there fixes?

Known issue amongst many folks across the platform. Search mobile presence and happy reading!