Alleluia exivi a patre et veni

The melody of this source is different from all others currently (Feb. '23) available on Cantus database. Modality, too, hovers across both authentic and plagal regions of G. 

The style of this Alleluia clearly resembles 16^th c., quasi post-Conciliar plainchant aesthetics in which only a few major words enclose melismas (here, patre and vado ad patrem) whereas all others are almost completely syllabic.