I have done so (though I found at least two further threads which address the problem, too, which I upvoted). Everybody who reads this please leave a positive vote on https://forum.duolingo.com/comment/28350397$comment_id%3D28350397 in order to enforce the procedure.
No, there is no difference and it is highly misleading for our learners to say what you are saying.
One can, when emphasizing the orthography, use some other I sound, narrower and wider and unnatural to Czech, but that does not mean there is any difference in i and y in Czech. The difference exists in Polish and dialects close to the Polish border may have this feature.