CZ IT is dire, like something from the mid-90s. I was unable to even look at my reservation online. After a lot of searching, I found a number for their London office (only by calling their AMS office...apparently operating into LHR for a year isn't enough time to list a contact number, even on the offical LHR website). I spoke to a very friendly lady who spoke super English, and helped me reserve specific seats over the phone.