Not too worried about the subtitles at this point.
I'm willing to bet that filmarena.cz has subtitle information for the regular Blu-ray release (Czech only) at the same level as in online Blu-ray/DVD stores in many countries; they often only specify subtitle tracks that are relevant to their main customer base.
Note that even now filmarena-eng.com (and filmarena.cz) has FAC Sicario subtitles specified as English SDH, English and Czech.
The Blu-ray disc included in the already released Czech Amaray has neither a Dolby Atmos soundtrack nor optional English subtitles, notwithstanding what is stated in the listing for the FAC edition.
On the FA site is an actual review of the Czech disc which details its technical specifications. I've included a link below. Use Google Chrome or similar to translate.
http://www.film-arena.cz/recenze/blu-ray-sicario-najemny-vrah
The above review clearly states that there are only two language tracks available on the disc: DTS-HD MA 5.1 English & Czech with subtitles only in Czech.
Clicking on the tab 'Videa' (Video) gives the option of viewing an unboxing video which includes the disc's actual menus. From 3m05s the menus displayed are those of the disc's audio and subtitle options. These confirm that the only two language tracks available are DTS-HD MA 5.1 English & Czech. There is no Dolby Atmos track. The only two subtitle options shown are Czech & None. There are no optional English subtitles.
The only way that this disc could have English subtitles is if they are hardcoded or burnt-in for those sections where Spanish is spoken. This seems unlikely, however, since there is no mention anywhere in the review of that being the case. Surely, someone must have access to a copy of the Czech disc that they can sample?
At the end of the day, the only way that the audio and subtitle details shown in the listing for the FAC edition can be correct, is if the disc is being re-authored especially for that edition, to include a Dolby Atmos track and either optional or hardcoded English subtitles. This seems a little extravagant given that this is a brand new release and surely, if that was the case, wouldn't it have been announced somewhere?
It would certainly be helpful if those in the know at FA were to throw some light on the subject before the GB commences.
should be enough for us all when the GB comes. 
Patiently waiting for the GB!!!!!!
