I was there on Saturday morning and it was a ZOO. The priority lane was inaccessible (closed), and when I asked, all I got was a shrug of the shoulders. So, it was off to immigration, where the lane controller tried (and failed ) to send me back to transit. Through immigration, through customs, go upstairs, through immigration, through security and into the lounge - all in about 6-7 minutes, much quicker than going the 'official' transit route.

TK really should do something about this. IST is a hub airport with gazillions of connections from early morning to late at night, and there is a very real chance of missing a connection because of the poor organisation here.