Generally, if your Simtek Sensor is working well there is no need to update. Only perform an update if Simtek suggests it. The most common reason is to force the sensor to connect to a new network or fix bugs in rare cases.
If you have manually turned off the LIGHT sensor switch, move it to the ON position before performing the update. This only pertains to customers with the 2nd-generation sensor who have manually switched OFF the light sensor, which is very rare. If that doesn't make sense to you, then it does not apply and you can follow the video to update.