I found the Czech references. https://www.zakonyprolidi.cz/cs/2013-186#p31 is the law, which went into effect in 2019. More explanation at https://www.mzv.cz/losangeles/en/consular_information/czech_citizenship_and_vital_records/children_and_grandchildren_of_former.html and https://www.svu2000.org/notices-archive/czech-citizenship-law/
I found the Czech references. https://www.zakonyprolidi.cz/cs/2013-186#p31 is the law, which went into effect in 2019. More explanation at https://www.mzv.cz/losangeles/en/consular_information/czech_citizenship_and_vital_records/children_and_grandchildren_of_former.html and https://www.svu2000.org/notices-archive/czech-citizenship-law/