in src/main/scala/com/gu/invoicing/preview/Impl.scala [194:203]
def findAffectedPublicationsWithRange(
publications: List[Publication],
start: LocalDate,
end: LocalDate,
): List[Publication] = {
publications
.filter(_.publicationDate.inClosedInterval(start, end))
.sortBy(_.publicationDate)
.distinct
}