I've been trying since yesterday morning to check in online but I kept getting a message telling me to phone customer service, which I did. I was told it wasn't a problem as I could check in at Manchester or I could keep trying. I decided to have another go this morning and was met with the same message. So again I rang customer service and she very kindly put all my details through only to be met with the same message! After speaking to a manager we have found out that online check in to turkey has to be done at the airport !! My question was simply " why hadn't we been informed of such changes?" Obviously she didn't know but would look into it. Hope this saves some people time and frustration.