Why does Sleep as Android recommend Airplane Mode during tracking?

I see it come up a lot… turn off wifi/mobile when sleep tracking is on. Why does Sleep as Android recommend this? I use DnD to prevent unwanted notifications. Does wifi/mobile interfere with the tracking somehow?

I don’t know why the app recommends it, but it’s probably better not to avoid unnecessary electromagnetic fields near your head while you sleep. When your phone is in DND mode, it’s still communicating with the mobile network, so the only way to turn off the radiation is via airplane mode.