Are you asking about Timed Access here?
If the default rule that you have for your network is "unlimited" access, then any device that has the password for the network can connect at any time.......unless......you have a set up a "rule" for that device that specifies when it can and cannot connect.
You would need to change the default rule for the network to No Access. Then, only the devices that you have specified in your "rules" will be allowed to connect to the network. Another device that might have the password for the network would not be able to connect unless it was listed as one of the clients with a connection "rule".
If you are saying that you do not have an Android device and one is connecting to your network, then you may have an unwanted guest. Change the name of your wireless network and change the password for the network.
"Hiding" your network is not even supported by any wireless industry standards. Anyone who wants to see your network can do so very easily. Sure, it might keep a few honest folks near you from seeing the name of your network. But, they are probably not the guys that you need to worry about.