If you google for "upgrade update galaxy s5 mini to 5.0 lollipop" you'll find some entries claiming that "I rewrite this tutorial from forum.xda-developers.com". Download links are provided, but the whole thing seems to be BS, just because:
- there is no reference to the "tutorial" cited, in the first place;
- whichever link I clicked at the menu ("home", "about us", etc) lead me to the very same page I landed at first;
- I changed the browser link from ".../samsung-galaxy-s5-mini-duos-6563.html" to "../samsung-galaxy-s6-mini-duos-6563.html" and I was taken to a page telling me how to... upgrade my "S6 Mini";
- as you may have guessed, changing the link to "...S19-mini-duos..." will also give a positive result, and the same goes with the Galaxy-XPTO97-mini-duos, of course.
So beware: downloading and installing those alleged "ROM upgrade files" could be a very dangerous project, to say the least. Take care.