Deus adjuvat me et dominus

Folio: 
095v
Sequence: 
7
Office/Mass: 
M
Genre: 
A
Position: 
3.1
Cantus ID: 
002165
Mode: 
8
Differentia: 
G1
Differentia database: 
Extra: 
084v
Indexing notes: 
Why are there two differentiae for this chant? (one at the bottom of f. 95v and one at the top of f. 96r)?