The Communio for the Baptism of the Lord has a change in the corrected editions (both in the Graduale Novum and in the Liber Gradualis) that puzzles me.

Here is the chant in the Graduale Triplex. At the end of the word "baptizati", the chant ends on "do"; the chant continues on the word "estis" on the same pitch: "do".



In both of the corrected editions, the first pitch on the word "estis" has been raised to "re". This is from the Graduale Novum, but the Liber Gradualis has made the same change.



There appears to be conflicting melodic instructions in the St. Gall neumes, with both a "r", indicating higher pitch, and an "e", indicating an equal pitch.

It appears the Triplex favored the "e" whereas the corrected editions favored the "r". I've begun to dabble in semiology, and I'm wondering why both of the corrected editions decided to make the same change from the Triplex. In most cases, I can easily see that the corrected editions got it right when they changed the melody. In this case, I'm perplexed.