Can you run some WiFi scanner at that time to see which devices are connected to your router at that time? I used Fing [1] on Android for that. This seems like

Can you run some WiFi scanner at that time to see which devices are connected to your router at that time? I used Fing [1] on Android for that. This seems like the simplest way. [1] https://www.fing.com/products/Fing-app https://www.fing.com/products/Fing-app