diff --git a/lib/include/srslte/upper/pdcp_entity_nr.h b/lib/include/srslte/upper/pdcp_entity_nr.h
index 7df9387f8..b00f33b9c 100644
--- a/lib/include/srslte/upper/pdcp_entity_nr.h
+++ b/lib/include/srslte/upper/pdcp_entity_nr.h
@@ -109,11 +109,11 @@ private:
  * Timer callbacks
  */
 // Reordering callback (t-Reordering)
-class pdcp_entity_nr::reordering_callback : public timer_callback
+class pdcp_entity_nr::reordering_callback
 {
 public:
   reordering_callback(pdcp_entity_nr* parent_) { parent = parent_; };
-  virtual void timer_expired(uint32_t timer_id) final;
+  void operator()(uint32_t timer_id);
 
 private:
   pdcp_entity_nr* parent;
diff --git a/lib/src/upper/pdcp_entity_nr.cc b/lib/src/upper/pdcp_entity_nr.cc
index 490b067fd..247924b2f 100644
--- a/lib/src/upper/pdcp_entity_nr.cc
+++ b/lib/src/upper/pdcp_entity_nr.cc
@@ -55,8 +55,7 @@ void pdcp_entity_nr::init(uint32_t lcid_, pdcp_config_t cfg_)
 
   // configure timer
   if (static_cast<uint32_t>(cfg.t_reordering) > 0) {
-    reordering_timer.set(static_cast<uint32_t>(cfg.t_reordering),
-                         [this](uint32_t tid) { reordering_fnc->timer_expired(tid); });
+    reordering_timer.set(static_cast<uint32_t>(cfg.t_reordering), *reordering_fnc);
   }
 
   // Mark entity as initialized 
@@ -332,7 +331,7 @@ void pdcp_entity_nr::deliver_all_consecutive_counts()
   }
 }
 
-void pdcp_entity_nr::reordering_callback::timer_expired(uint32_t timer_id)
+void pdcp_entity_nr::reordering_callback::operator()(uint32_t timer_id)
 {
   parent->log->debug("Reordering timer expired\n");