Depending on the species, swallows generally have a lifespan of four or five years. So depending on their age, the swallows in Unknown Caller probably died before the end of the 360 tour.— U2gigs (@u2gigs) May 21, 2020
Originally posted by iTim:[..]
Sad news. I loved their work, they became an integral part of the tour, may they rest peacefully.