diff --git a/R/inner_combine_linter.R b/R/inner_combine_linter.R
index b83a120a3..bac85955e 100644
--- a/R/inner_combine_linter.R
+++ b/R/inner_combine_linter.R
@@ -6,6 +6,13 @@
 #'   preferred so that the most expensive part of the operation ([as.Date()])
 #'   is applied only once.
 #'
+#' Note that [strptime()] has one idiosyncrasy to be aware of, namely that
+#'   auto-detected `format=` is set by the first matching input, which means
+#'   that a case like `c(as.POSIXct("2024-01-01"), as.POSIXct("2024-01-01 01:02:03"))`
+#'   gives different results to `as.POSIXct(c("2024-01-01", "2024-01-01 01:02:03"))`.
+#'   This false positive is rare; a workaround where possible is to use
+#'   consistent formatting, i.e., `"2024-01-01 00:00:00"` in the example.
+#'
 #' @examples
 #' # will produce lints
 #' lint(
diff --git a/man/inner_combine_linter.Rd b/man/inner_combine_linter.Rd
index 73ac594e2..6455f5d68 100644
--- a/man/inner_combine_linter.Rd
+++ b/man/inner_combine_linter.Rd
@@ -13,6 +13,14 @@ The same equivalence holds for several other vectorized functions like
 preferred so that the most expensive part of the operation (\code{\link[=as.Date]{as.Date()}})
 is applied only once.
 }
+\details{
+Note that \code{\link[=strptime]{strptime()}} has one idiosyncrasy to be aware of, namely that
+auto-detected \verb{format=} is set by the first matching input, which means
+that a case like \code{c(as.POSIXct("2024-01-01"), as.POSIXct("2024-01-01 01:02:03"))}
+gives different results to \code{as.POSIXct(c("2024-01-01", "2024-01-01 01:02:03"))}.
+This false positive is rare; a workaround where possible is to use
+consistent formatting, i.e., \code{"2024-01-01 00:00:00"} in the example.
+}
 \examples{
 # will produce lints
 lint(