diff --git a/R/add_case.R b/R/add_case.R
index e5336f9..07642a6 100644
--- a/R/add_case.R
+++ b/R/add_case.R
@@ -5,13 +5,13 @@
 add_case <- function(data, cutoff = 20) {
 # TODO: What is the best choice for the cutoff here?
 
-  data$timediff   <- as.numeric(diff(c(data$date.start, utils::tail(data$date.start, 1))))
-  data$timeindex  <- ifelse(data$timediff <= cutoff, 0, 1)
-  case_change     <- diff(c(0, c(which(data$timeindex == 1), nrow(data))))
-  data$case       <- rep(seq_along(case_change), case_change)
+  data$timediff  <- -c(utils::head(data$date.stop, nrow(data) - 1) - data$date.start[-1], 0)
+  data$timeindex <- ifelse(data$timediff <= cutoff, 0, 1)
+  case_change    <- diff(c(0, c(which(data$timeindex == 1), nrow(data))))
+  data$case      <- rep(seq_along(case_change), case_change)
 
-  data$timediff   <- NULL
-  data$timeindex  <- NULL
+  data$timediff  <- NULL
+  data$timeindex <- NULL
 
   data
 }
diff --git a/R/create_eventlogs.R b/R/create_eventlogs.R
index 80f3d5c..170a2c5 100644
--- a/R/create_eventlogs.R
+++ b/R/create_eventlogs.R
@@ -14,12 +14,13 @@
 #' @param glossar Logical indicating if glossar folder is present and if it
 #' should be taken into account when preprocessing raw log files. Default
 #' is FALSE.
+#' @param save Temporary argument to save intermediate data frames for debugging.
 #' @return Data frame.
 #' @export
 #' @examples
 #' # tbd
 create_eventlogs <- function(data, xmlpath = NULL, case_cutoff = 20,
-                             rm_nochange_moves = TRUE, glossar = FALSE) {
+                             rm_nochange_moves = TRUE, glossar = FALSE, save = FALSE) {
 
   if (!lubridate::is.POSIXt(data$date)){
     cat("########## Converting variable `date` to POSIXct ##########", "\n")
@@ -128,6 +129,8 @@ create_eventlogs <- function(data, xmlpath = NULL, case_cutoff = 20,
     dat7$glossar <- NULL
   }
 
+  if (save) save(dat, dat1, dat2, dat3, dat4, dat5, dat6, dat7, file = "../data/tmp_intermediate-df.RData")
+
   dat7
 }
 
diff --git a/man/create_eventlogs.Rd b/man/create_eventlogs.Rd
index aa8de43..c775370 100644
--- a/man/create_eventlogs.Rd
+++ b/man/create_eventlogs.Rd
@@ -9,7 +9,8 @@ create_eventlogs(
   xmlpath = NULL,
   case_cutoff = 20,
   rm_nochange_moves = TRUE,
-  glossar = FALSE
+  glossar = FALSE,
+  save = FALSE
 )
 }
 \arguments{
@@ -28,6 +29,8 @@ removed. Default is TRUE.}
 \item{glossar}{Logical indicating if glossar folder is present and if it
 should be taken into account when preprocessing raw log files. Default
 is FALSE.}
+
+\item{save}{Temporary argument to save intermediate data frames for debugging.}
 }
 \value{
 Data frame.