Yup zero info from Ford and or the suppliers. But of course magazines are happy to report. But what they've put out so far is so much conflicting info.
Car mags in Australia have released "insider" info of them just receiving what is basically our current year ST, which is actually an upgrade to they currently have.
Ford Brasil has also released a bit of info on engines and they have spotted these test cars running around with a covered badge under the Fiesta name, but mostly likely it's the turbo 1.0 model. There is also the new revised Ecosport being released Nov. (same platform as Fiesta)
https://salaodocarro.com.br/segredos/novo-ford-fiesta-flagrado-testes.html
http://carplace.uol.com.br/ford-fiesta-1-0-ecoboost-comeca-a-ser-vendido-no-brasil-em-maio/
Mags in UK have released these renderings and info.
http://www.autoexpress.co.uk/ford/fiesta/93556/new-2017-ford-fiesta-pictures-specs-and-release-date
And then of course we've all seen these pictures. Which were reported as an RS, but who knows, I don't believe it was ever revealed what it really was.
Considering what Ford has done. The RS, testing Ecosports, retooling factories, moving production, introducing a limited ST200, Looking at the ST history in EU there was a hiatus when the new gen came around. We got introduced to the NA model at LAAS 2012 as part of the refresh. Considering all this I'm led to believe that the 16 is the last model year for the current-gen ST.
Now in your situation you could wait until mid-late summer when Ford announces new models and holds a majority of it's press releases to find out if this is the last year. If it is, and you have the means to do so, get one. Usually dealers will want to get rid of them quickly as well. But I'll advise to you though that many other people will be of the same mindset, wanting snatch up those last STs so you may not get your pick or the best deal.
If they release a new model, some people will be trading in 16s with less than 10,000 on the clock for the back-up cameras, new look and what not and these trade-ins will most likely be even more discounted, if you're open to slightly-used car.
Edit: Just found this link to a press release relating to Europe.
http://www.slideshare.net/indianautosblog/next-gen-ford-fiesta-cologne-germany-production