I know this piece since my studies at the college. Its Messiaen-like but with own favour and style. A good piece! The Alleluyas is out of the Liturgy of St. James: "At his feet the six-winged Seraph; Cherubim with sleepless eye, Veil their faces to the Presence, as with ceaseless voice they cry, Alleluya, Alleluya, Alleluya, Lord most high"
Therefore I transport the good Haverhill acoustically in the York Minster.
And I attached the midi file - because I want to hear the piece on the Hereford Father Willis organ. Please feel free :-)