I’m aware of Canon 917 which explains that the Eucharist can be received twice in one day provided the second reception is within a eucharistic celebration. I’m unclear if that is a 24-hour day or if it would include a vigil mass.
The specific situation: I’m in the music ministry at our parish. If I commune at the Saturday evening vigil mass (5 pm), then also commune at a Sunday morning mass, can I commune again at the Sunday evening mass (5 pm)? Would that count as three times in the same day (counting Sat. vigil as part of Sunday), or only twice (once on Sat. and twice on Sun.)?