I just wanted to reiterate the comment that the fare that they are calling Latitude is not really an AC fare using their branded structure - it is a standard IATA fare called YFF77 - which is the most expensive price essentially you can sell a fare at and is used by many airlines. There is a long list of things you can complain about with fares and this is one for sure. They basically are not offering Lat fares out of Europe. However - here's another one - they are basically not offering J-Class fares out of Canada that are changeable or refundable for free while ex-Europe it is somewhat easy to do. So - now I have my B-Fares out of Canada and my J-fares out of Europe with some combination of overlapping tickets needing a spaghetti chart to remind me which tickets are active at any time.

Edit - Looking at the fare setup - you are best to book PY Flexible I suppose - and some of the O Fares are super flexible but I do agree - they are quite a bit more expensive than the Lat fares ex Canada . But they are cheaper than the YWW77 fare types.