Just want to let you guys know that bug is still there i experienced it twice in 1 game
1st came a scout, and it decided to go wandering off outside of the grav well at sublight speed... Unfortunetly my hanger defense fighters decided to go follow it. It looked like it was following the phase lane, but it was moving at sublight, and it still showed as being at the world it just left from.

Same thing happened later but this time my garrison fleet was there. good thing i set aggression to hold position (all but the fighters). All the strike craft tried to chase the scout outside the grav well. If i had aggression set to grav well the whole fleet would have followed.