diff --git a/bertrend/BERTrend.py b/bertrend/BERTrend.py
index 42d4679..ce2a4e5 100644
--- a/bertrend/BERTrend.py
+++ b/bertrend/BERTrend.py
@@ -649,11 +649,13 @@ def save_models(self, models_path: Path = MODELS_DIR):
             topic_model.topic_info_df.to_pickle(model_dir / TOPIC_INFO_DF_FILE)
 
         # Serialize BERTrend (excluding topic models for separate reuse if needed)
-        topic_models_bak = copy.deepcopy(self.topic_models)
-        self.topic_models = None
+        # topic_models_bak = copy.deepcopy(self.topic_models)
+        # FIXME: the commented code introduced a too-heavy memory overhead, to be improved; the idea is to serialize
+        # the topics models separetely from the rest of the BERTrend object
+        # self.topic_models = None
         with open(models_path / BERTREND_FILE, "wb") as f:
             dill.dump(self, f)
-        self.topic_models = topic_models_bak
+        # self.topic_models = topic_models_bak
 
         logger.info(f"Models saved to: {models_path}")
 
diff --git a/bertrend_apps/prospective_demo/dashboard_common.py b/bertrend_apps/prospective_demo/dashboard_common.py
index 5d67cc5..22bcac6 100644
--- a/bertrend_apps/prospective_demo/dashboard_common.py
+++ b/bertrend_apps/prospective_demo/dashboard_common.py
@@ -29,6 +29,14 @@ def get_df_topics(model_interpretation_path=None) -> dict[str, pd.DataFrame]:
 
 def update_key(key: str, new_value: Any):
     st.session_state[key] = new_value
+    # reset ts value in order to avoid errors if a previous ts value is not available for the new key value
+
+
+def update_key_and_ts(key: str, new_value: Any):
+    update_key(key, new_value)
+    # reset ts value in order to avoid errors if a previous ts value is not available for the new key value
+    if "reference_ts" in st.session_state:
+        del st.session_state["reference_ts"]
 
 
 def choose_id_and_ts():
@@ -43,7 +51,9 @@ def choose_id_and_ts():
             options=options,
             index=options.index(st.session_state.model_id),
             key=model_id_key,  # to avoid pb of unicity if displayed on several places
-            on_change=lambda: update_key("model_id", st.session_state[model_id_key]),
+            on_change=lambda: update_key_and_ts(
+                "model_id", st.session_state[model_id_key]
+            ),
         )
     with col2:
         list_models = get_models_info(model_id)
@@ -58,7 +68,7 @@ def choose_id_and_ts():
         if "reference_ts" not in st.session_state:
             st.session_state.reference_ts = list_models[-1]
         ts_key = uuid.uuid4()
-        reference_ts = st.select_slider(
+        st.select_slider(
             "Date d'analyse",
             options=list_models,
             value=st.session_state.reference_ts,
diff --git a/bertrend_apps/prospective_demo/models_info.py b/bertrend_apps/prospective_demo/models_info.py
index 9a98783..b3099b4 100644
--- a/bertrend_apps/prospective_demo/models_info.py
+++ b/bertrend_apps/prospective_demo/models_info.py
@@ -222,7 +222,7 @@ def handle_regenerate_models(row_dict: dict):
     with col1:
         if yes_btn := st.button("Oui", type="primary"):
             # Delete previously stored model
-            # delete_cached_models(model_id)
+            delete_cached_models(model_id)
             logger.info(f"Modèles en cache supprimés pour la veille {model_id} !")
 
             # Regenerate new models