In case anyone else may read Anit’s answer and misinterpret it, when he says “Only while applying updates in the default instance, it prompts you, to apply it on rest of the instances”, he means very specifically that when applying updates/hotfixes, such as when using the Server Update>Updates page of the CF Admin. One could read his comment to mean “while applying updates” to other Admin settings, so I thought this worth clarifying for folks.
/charlie