It's really a prayer that honors the Virgin Mary and seeks her intercession. The specific timing of when it's prayed may change determined by individual or community practices. The hymn is sung (using the English translation "Hail, Holy Queen enthroned earlier mentioned") by a choir of nuns inside the 1992 https://encapsuladosvip.com/vita-pro-nobis-descubra-os-beneficios-dessa-incrivel-planta-medicinal/