Yup. 10 hours of Play time, not activation time.
Most “reviews” of Star Wars Battlefront were from people playing (on Xbox One) in that 10 hour span and wanting to publish their review before anyone else (believe EA did not have a media pre-launch event).
Unravel, releasing Feb 4th, will be restricted to the first 2 levels also. I imagine shorter games will have such restrictions.
The 10% discount seems less valuable as PC codes are discounted heavily. On the Xbox One, its a pretty good deal as digital items are rarely discounted that much. Especially DLC and digital copies at launch.