Fire tower lights do not change when held down in StrategyGame on iOS

The fire tower charge effect is not working correctly on iOS. This was tested with an iPhone6S_6240 OS: 9.3.2

Does not occur on Android. Tested on Galaxy S7

1. Obtain StrategyGame from the launcher
2. Open in the editor
3. Launch on to iOS device
4. Build a Fire Tower
5. Press and hold the fire tower once it is built

Result: The fire tower light is always fully lit and does not change

Expected: The fire tower is supposed to be unlit and then gradually change to lit as it is held down