Hi Leyth centurian.
You are far from the first person to have this question. As the CT is a very slow seller many bikes were first registered a year or maybe 2 after the were built. My current CT is a 2015 model (Silver and black tank) on a 66 plate but actually first registered 1st Jan 2017. I knew this when i bought it new and got a deal on it.
2016 onwards
Model year CTs have the adjustable screen as well as a couple of other changes. The DCT has 3 sport modes where as previous models have just D and S. the area around the instruments is slightly different aswell.
Copied from an old MCN article:
2016 Honda VFR11200X Crosstourer
The range-topping Honda VFR1200X has been given a number of minor updates for 2016 which includes a new manually-adjustable windscreen, updates to the Dual Clutch Transmission (DCT) and software updates that help the DCT to work better on hills.
Honda’s press release explains: “There are now three levels of S mode for the DCT) version to cover a wider range of riding scenarios and styles. Software upgrades that allow the machine to detect uphill and downhill slopes and adjust its shift pattern accordingly. The DCT option has been chosen by the majority of VFR1200X Crosstourer customers since 2014.”
A new Special Edition colour of Candy Prominence Red and Graphite Black is also now available.
https://www.motorcyclenews.com/news/new-bikes/2015/october/honda-reveals-updated-nc750x-and-cb500x-for-2016/The key thing to identify is the model year not the registration year.
Despite these differences there isnt really a lot in it and pre 2016 bikes are not EU4 either which maybe a slight advantage. Ive also heard that they some who ordered 2016 on Highlanders didnt get spot lights as part of the package.
Hope this helps.