For those of you in the Xbox Preview Program, The Xbox Team released a new firmware update for the Xbox One Controller (version 1.2.2236.0.)
This new update cuts the console to controller connectivity time in half from 4-5 seconds to a quick 2 seconds. In addition, a myriad of smaller issues, as detailed from Preview Program users, were addressed and fixed, for stability purposes.
To update your controller now, make sure your console is updated to the newest preview firmware that is currently rolling out to Preview Program users (6.2.12117.0 (xb_rel_1502.150122-2300)) and go to Settings > Devices and Accessories, select your controller, and select Update. Remember, to update, your controller must be connected via USB cable.
Source: Major Nelson