квартальный день означает в английский

quarter day▼(each of the four days starting a new quarter year)
noun
[UK: ˈkwɔː.tə(r) deɪ] [US: ˈkwɔːr.tər ˈdeɪ]

quarter-day▼(each of four days on which rents due)
noun
[UK: ˈkwɔː.tə(r) deɪ] [US: ˈkwɔːr.tər ˈdeɪ]