There are quite a lot of Trajectory world leakages.

[23:46:24] [Server thread/DEBUG] [FML/]: The world 241f1cbb (Trajectory_TheWorldForMe) may have leaked: seen 415 times.
[23:46:24] [Server thread/DEBUG] [FML/]: The world 48bb777e (Trajectory_TheWorldForMe) may have leaked: seen 415 times.
[23:46:24] [Server thread/DEBUG] [FML/]: The world 38140f5e (Trajectory_TheWorldForMe) may have leaked: seen 415 times.
[23:46:24] [Server thread/DEBUG] [FML/]: The world 32f1ee70 (Trajectory_TheWorldForMe) may have leaked: seen 415 times
[23:46:24] [Server thread/DEBUG] [FML/]: The world 2df4e30e (Trajectory_TheWorldForMe) may have leaked: seen 415 times.
[23:46:24] [Server thread/DEBUG] [FML/]: The world 48e309fd (Trajectory_TheWorldForMe) may have leaked: seen 415 times.
[23:46:24] [Server thread/DEBUG] [FML/]: The world 7eb23601 (Trajectory_TheWorldForMe) may have leaked: seen 415 times.
[23:46:24] [Server thread/DEBUG] [FML/]: The world 52a48324 (Trajectory_TheWorldForMe) may have leaked: seen 415 times.

And number still raises.

That's really weird... Though I'm managing fake worlds in a way I wouldn't really advise... I'll look into it for the last 1.7.10 update, but I can't assure I'll figure it out. The (upcoming) 1.8.9/1.9 version doesn't do it like this so it should work well.