I can understand. I would also prefer to choose the time before it disconnects.
I am running iOS, but some of my friends are running Android without (those big) problems.
Maybe you could try to remove the go plus from your phone by ‘forgetting’ the connection and then reset the go plus.
After that try to link it with your phone again.
To hard rest your Pokemon Go Plus device, hold the center button for just over 5 seconds, or until it turns solid blue. Let go, then press the button again for another 5 seconds, until it buzzes.