Elsewhere, her feast is January 1, which is the anniversary of her death. It's also the Solemnity of Mary the Mother of God, so St. Zdislava's feast is not observed liturgically.
Except by her fellow Dominicans, who have moved her feast day to January 4. Which is also the Memorial of St. Elizabeth Ann Seton, so St. Zdislava's feast is not observed liturgically by the Dominican Provinces of the U.S.
Which is why I observe it on May 30.
This is also the centenary of her beatification. (And no, I didn't realize my webpage on her was linked on the Press Office of the Czech Bishops' Conference page announcing the commemoration of the centenary.)