Players of whom are not subscribed to FlyOrDie games get a Be Right Back (clock) status after being in-active for 120 seconds and therefore, they don't have the option to enable this feature themselves.
As soon as they become active again, the clock is removed from their status.
Subscribers are able to enable this feature when ever they like.
The reason being for non-subscribers having this option is... It gives users notice that that particular player may not accept a challenge due to being in-active for a certain amount of time.
This isn't abuse of features, it just saves others time.
Kind Regards,
Sullivan88