Kicked out of mount during quest.

Hello. I've been leveling in Wintergarde and got a quest The Hills Have Us, after accepting it I hopped onto gryphon with dwarf rider but after while game kicks me from it and I start to fall down with a parachute. So I cannot get to Amberpine Lodge in Grizzly Hills by flying. I am sure it happened to my friend long ago but he was flying from Dalaran to Skybreaker ship in Icecrown, after leaving Dalaran zone he was kicked out too with parachute on him.

Has anything like that happened to someone else? Is it bug? I have no addons installed.

This is a phasing issue. Because of the phasing Horde players can't complete "Riding the red rocket" quest in Grizzly Hills, your rocket disappears just before you reach the target ship because you phase into the Frozen Sea instead of Grizzly Hills.

And is there a way to fix it? /reload relog or anything like that did not help.