diff --git a/R/staging_is_active.R b/R/staging_is_active.R
index 4d07c66..904490f 100644
--- a/R/staging_is_active.R
+++ b/R/staging_is_active.R
@@ -3,25 +3,30 @@
 #' @family staging
 #' @description Check if the stating universe is active.
 #' @return `TRUE` if the staging universe is active, `FALSE` otherwise.
-#' @param thresholds Character vector of `"%m-%d"` dates that the
+#' @param start Character vector of `"%m-%d"` dates that the
 #'   staging universe becomes active. Staging will then last for a full calendar
-#'   month until, but not including, the same date a month later.
+#'   month. For example, if you supply a start date of `"01-15"`,
+#'   then the staging period will include all days from `"01-15"` through `"02-14"`
+#'   and not include `"02-15"`.
 #' @param today Character string with today's date in `"%Y-%m-%d"` format or an
 #'   object convertible to POSIXlt format.
 #' @examples
 #' staging_is_active()
 staging_is_active <- function(
-  thresholds = c("01-15", "04-15", "07-15", "10-15"),
+  start = c("01-15", "04-15", "07-15", "10-15"),
   today = Sys.Date()
 ) {
-  today <- as.POSIXlt(today, tz = "UTC")
-  within_freeze <- function(x, today) {
-    mon <- today$mon + 1L
-    day <- today$mday
-    mon == x[1L] && day >= x[2L] || mon == x[1L] + 1L && day < x[2L]
-  }
-  thresholds <- strsplit(thresholds, split = "-", fixed = TRUE)
-  thresholds <- lapply(thresholds, as.integer)
-  within <- lapply(thresholds, within_freeze, today = today)
-  any(as.logical(within))
+   today <- as.POSIXlt(today, tz = "UTC")
+   start <- strsplit(start, split = "-", fixed = TRUE)
+   start <- lapply(start, as.integer)
+   within <- lapply(start, within_staging, today = today)
+   any(as.logical(within))
+}
+
+within_staging <- function(start, today) {
+  month <- today$mon + 1L
+  day <- today$mday
+  stopifnot(day <= 28L)
+  (month == start[1L] && day >= start[2L]) ||
+    (month == start[1L] + 1L && day < start[2L])
 }