diff --git a/implementation/endpoints/include/buffer.hpp b/implementation/endpoints/include/buffer.hpp
index af0582d2e..56f31c31a 100644
--- a/implementation/endpoints/include/buffer.hpp
+++ b/implementation/endpoints/include/buffer.hpp
@@ -55,6 +55,9 @@ struct train {
         departure_ = departure_timer_->expires_from_now();
         boost::system::error_code ec;
         departure_timer_->cancel(ec);
+        if (departure_.count() < 0) {
+            departure_ = std::chrono::nanoseconds::zero();
+        }
     }
 };
 
diff --git a/implementation/endpoints/src/server_endpoint_impl.cpp b/implementation/endpoints/src/server_endpoint_impl.cpp
index 90aea966b..b75605500 100644
--- a/implementation/endpoints/src/server_endpoint_impl.cpp
+++ b/implementation/endpoints/src/server_endpoint_impl.cpp
@@ -297,10 +297,8 @@ bool server_endpoint_impl<Protocol>::send_intern(
             _data[VSOMEIP_METHOD_POS_MAX]);
 
     std::chrono::nanoseconds its_debouncing(0), its_retention(0);
-    if (its_service != VSOMEIP_SD_SERVICE && its_method != VSOMEIP_SD_METHOD) {
-        get_configured_times_from_endpoint(its_service, its_method,
+    get_configured_times_from_endpoint(its_service, its_method,
                 &its_debouncing, &its_retention);
-    }
 
     // STEP 4: Check if the passenger enters an empty train
     const std::pair<service_t, method_t> its_identifier = std::make_pair(
@@ -308,39 +306,14 @@ bool server_endpoint_impl<Protocol>::send_intern(
     if (target_train->passengers_.empty()) {
         target_train->departure_ = its_retention;
     } else {
-        if (target_train->passengers_.end()
-                != target_train->passengers_.find(its_identifier)) {
-            must_depart = true;
-        } else {
             // STEP 5: Check whether the current message fits into the current train
             if (target_train->buffer_->size() + _size > endpoint_impl<Protocol>::max_message_size_) {
                 must_depart = true;
             } else {
-                // STEP 6: Check debouncing time
-                if (its_debouncing > target_train->minimal_max_retention_time_) {
-                    // train's latest departure would already undershot new
-                    // passenger's debounce time
-                    must_depart = true;
-                } else {
-                    if (its_debouncing > target_train->departure_) {
-                        // train departs earlier as the new passenger's debounce
-                        // time allows
-                        must_depart = true;
-                    } else {
-                        // STEP 7: Check maximum retention time
-                        if (its_retention < target_train->minimal_debounce_time_) {
-                            // train's earliest departure would already exceed
-                            // the new passenger's retention time.
-                            must_depart = true;
-                        } else {
-                            if (its_retention < target_train->departure_) {
-                                target_train->departure_ = its_retention;
-                            }
-                        }
+                    if (its_retention < target_train->departure_) {
+                        target_train->departure_ = its_retention;
                     }
-                }
             }
-        }
     }
 
     // STEP 8: if necessary, send current buffer and create a new one