This sentence on the club hotel flight package trip is interesting:
."Fans will be required to use UEFA Mobility to travel to and from the Stadium on the day of the match"
This is what it says for the day trip:
"Upon arrival, UEFA-provided Shuttle Buses will take fans direct from the airport to the fan zones at Atatürk Olympic Stadium"
I can't find anything online about "UEFA Mobility" however there has been a lot of work. liaison with fans etc to avoid the problems in Paris.
I suspect they might cordon off the Stadium and only allow access via UEFA Buses, so people without tickets, can't get anywhere near the stadium.
It's worth keeping an eye on this one, catching a cab might be a huge mistake.
Does Alex at City Matters have any idea about this?