2x Bonus Train

[iptables]

Had absolutely the same question few weeks ago as yours )
Answer : It resets, when your vids are reseted. Means, when you have your vids for watching available = you have 2x as well.
It drains a free video btw.
To use it properly, select minimum 8 players to train, and the 2x will be there for you. That ofcourse is, if you haven't already watched ALL your daily vids
The same goes for the individual train player training via free heal/moral/injury boost.