I have noticed a problem wich i gues is NVDA-related. Because when I'M visit.
vich is Swedish railway-company. In that calender i can not toggle betwean month when i made a booking using NVDA anf Firefox. But if i use NVDA and IE, Jaws and firefox it i can se the buton next and previus. but not NVDA and firefox. for some reason i cant se those butons.
There is even an english version wich you can change to in the top of the site. So i would be glad if some developer can have a look at this.