M3 products cut the power of WLAN module when the device enters SLEEP mode (or STANDBY mode in your terminology) regardless of the Power Save mode in Summit Client Utility (SCU).
And upon waking up, it provides the power to the module again and tries re-connecting.
In SCU, wake up refers to checking existence of packets to be sent or received. In other words, while maintaining the connection with an access point, it wakes up to check the packets.
Constantly Awake Mode (CAM) means constantly draws the maximum power to communicate with an AP. So that it can maintain the reliable connectivity.
In other power save modes, such as Maximum and Fast, only wakes up periodically to check the existence of the packet.
This is the concept of the design.
If you think this may cause problem, you can block entering sleep mode. Turing off the back light instead of entering the sleep mode may be a solution. However, this method will draw much more current from the battery and will shorten the battery durability
