Kerim Frei posted on twitter that he's in Istanbul.
Landed in Istanbul!— Kerim Frei (@KerimFrei21) September 1, 2013
This links up well with the rumors that he's moving to Besiktas.
At the same time, reports are that Jol is only interested in loaning him, not selling him. I'm pretty confident that Frei won't be a Fulham player this season, whether he's back or not next year remains to be seen.