diff --git a/R/sim_fixed_n.R b/R/sim_fixed_n.R
index c573111a..edd5f90e 100644
--- a/R/sim_fixed_n.R
+++ b/R/sim_fixed_n.R
@@ -51,6 +51,20 @@
 #'   (1 and 2).
 #' - `5`: The maximum of targeted event count and minimum follow-up cuts
 #'   (2 and 3).
+#' 
+#' For custom timing options beyond the 5 predefined ones above,
+#' please instead use [sim_pw_surv()] function to generate time-to-event data
+#' and [get_analysis_date()] to calculate timing.
+#' Refer to the vignette on [Custom Fixed Design Simulations](https://merck.github.io/simtrial/articles/sim_fixed_design_custom.html)
+#' for a detailed tutorial.
+#' 
+#' If you are doing a custom fixed design simulation, you are not limited to the logrank or weighted logrank (Fleming-Harrington) tests.
+#' The following are supported: RMST via [rmst()], weighted logrank tests
+#' via [wlr()] (including Fleming-Harrington, Magirr-Burman, and Xu2017 weights),
+#' and MaxCombo test via [maxcombo()]. 
+#' Refer to the vignette on [Custom Fixed Design Simulations](https://merck.github.io/simtrial/articles/sim_fixed_design_custom.html)
+#' for a detailed tutorial.
+#'
 #'
 #' @return
 #' A data frame including columns:
diff --git a/man/sim_fixed_n.Rd b/man/sim_fixed_n.Rd
index 76642a14..b74688ed 100644
--- a/man/sim_fixed_n.Rd
+++ b/man/sim_fixed_n.Rd
@@ -80,6 +80,19 @@ for data cutoff:
 \item \code{5}: The maximum of targeted event count and minimum follow-up cuts
 (2 and 3).
 }
+
+For custom timing options beyond the 5 predefined ones above,
+please instead use \code{\link[=sim_pw_surv]{sim_pw_surv()}} function to generate time-to-event data
+and \code{\link[=get_analysis_date]{get_analysis_date()}} to calculate timing.
+Refer to the vignette on \href{https://merck.github.io/simtrial/articles/sim_fixed_design_custom.html}{Custom Fixed Design Simulations}
+for a detailed tutorial.
+
+If you are doing a custom fixed design simulation, you are not limited to the logrank or weighted logrank (Fleming-Harrington) tests.
+The following are supported: RMST via \code{\link[=rmst]{rmst()}}, weighted logrank tests
+via \code{\link[=wlr]{wlr()}} (including Fleming-Harrington, Magirr-Burman, and Xu2017 weights),
+and MaxCombo test via \code{\link[=maxcombo]{maxcombo()}}.
+Refer to the vignette on \href{https://merck.github.io/simtrial/articles/sim_fixed_design_custom.html}{Custom Fixed Design Simulations}
+for a detailed tutorial.
 }
 \examples{
 \dontshow{if (requireNamespace("dplyr", quietly = TRUE)) withAutoprint(\{ # examplesIf}