For those who are having issues with Instant On not working after putting the computer to sleep there is a quick fix to correct this. It seems the settings for Hibernate Time doesn't take until you go into the Old Power Settings screen, modify the Hibernate After time, apply the change, and then change it back to 360minutes (6 hours). Once you do this Instant On will work as expected within 6 hours of last using the device. Steps to make this change are:
- Click start and type in 'Power'
- From the list of options select 'Edit Power Plan'
- From the Window select the 'Change default settings for this plan'
- The Advanced Settings should now be open. Expand 'Sleep', 'Hibernate after'.
- Modify the On Battery option to be something other than 360, and the Plugged in to be something other than 0 and click apply.
- Change the settings back to 360 and 0 and click Apply again.
Instant On should now be working correctly. I've done it on mine and it is now QUICK to start up as long as it's been less than 6 hours or my Surface has been plugged in.
If you want the Instant On to be longer than 6 hours, adjust the On battery option to be higher. Just be aware that while in Connected Standby sleep and not Hibernated that there will be higher battery drain.