The rain sensor itself has a mechanism to set delay time — generally through controlling the evaporation inside the sensor. After raining, the sensor can remain activated for maybe a day, which explains why it’s still reporting rain detected after a day. You can check the rain sensor to see. If it’s NC, that means when it’s activated its two wires are open (not connected). This is something easy to check with a multimeter.
Again, the 10 hours you set does NOT apply to rain sensor — it only applies to weather adjustment method, which uses online weather data, not your rain sensor.