Castro resigning

Castro announces that he is resigning office on sunday.

Just heard some of the US presidential candidates comment on that piece of news on CNN: "Essential first step, but it is sadly insufficient in bringing freedom to Cuba", that: "There is still a long way towards human rights", "mark the end of a dark era in Cuba's history.", a need for: "The prompt release of all prisoners of conscience wrongly jailed"

Is this about Castro resigning or the closing of Gitmo?