diff --git a/neptun/src/noise/timers.rs b/neptun/src/noise/timers.rs
index 6cce8df..a231128 100644
--- a/neptun/src/noise/timers.rs
+++ b/neptun/src/noise/timers.rs
@@ -67,8 +67,7 @@ pub enum TimerName {
 }
 
 impl TimerName {
-    pub const VALUES: [Self; TimerName::Top as usize] = [
-        Self::TimeCurrent,
+    pub const VALUES: [Self; TimerName::Top as usize - 1] = [
         Self::TimeSessionEstablished,
         Self::TimeLastHandshakeStarted,
         Self::TimeLastPacketReceived,
@@ -215,6 +214,14 @@ impl Tunn {
         }
     }
 
+    fn tick_marked_timers(&mut self, timer_mask: u16) {
+        for timer_name in TimerName::VALUES {
+            if (timer_mask & (1 << (timer_name as u16))) != 0 {
+                self.timer_tick(timer_name);
+            }
+        }
+    }
+
     pub fn update_timers<'a>(&mut self, dst: &'a mut [u8]) -> TunnResult<'a> {
         let mut handshake_initiation_required = false;
         let mut keepalive_required = false;
@@ -234,16 +241,8 @@ impl Tunn {
         let timer_mask = self
             .timers
             .timers_to_update_mask
-            .load(std::sync::atomic::Ordering::Relaxed);
-        for timer_name in TimerName::VALUES {
-            if (timer_mask & (1 << (timer_name as u16))) != 0 {
-                self.timer_tick(timer_name);
-            }
-        }
-        // Reset all marked bits
-        self.timers
-            .timers_to_update_mask
-            .store(0, std::sync::atomic::Ordering::Relaxed);
+            .swap(0, std::sync::atomic::Ordering::Relaxed);
+        self.tick_marked_timers(timer_mask);
 
         self.update_session_timers(now);
 
@@ -429,7 +428,7 @@ mod tests {
     use super::TimerName;
 
     #[test]
-    fn create_two_tuns() {
+    fn test_update_marked_timers() {
         let my_secret_key = x25519_dalek::StaticSecret::random_from_rng(OsRng);
         let my_idx = OsRng.next_u32();
 
@@ -469,4 +468,41 @@ mod tests {
         assert!(my_tun.timers[TimerName::TimeLastDataPacketReceived].is_zero());
         assert!(my_tun.timers[TimerName::TimePersistentKeepalive].is_zero());
     }
+
+    #[test]
+    fn test_mark_timers_during_update() {
+        let my_secret_key = x25519_dalek::StaticSecret::random_from_rng(OsRng);
+        let my_idx = OsRng.next_u32();
+
+        let their_secret_key = x25519_dalek::StaticSecret::random_from_rng(OsRng);
+        let their_public_key = x25519_dalek::PublicKey::from(&their_secret_key);
+
+        let mut my_tun =
+            Tunn::new(my_secret_key, their_public_key, None, None, my_idx, None).unwrap();
+
+        // Mark timers to update
+        my_tun.mark_timer_to_update(super::TimerName::TimeLastDataPacketSent);
+
+        let timer_mask = my_tun
+            .timers
+            .timers_to_update_mask
+            .swap(0, std::sync::atomic::Ordering::Relaxed);
+
+        my_tun.mark_timer_to_update(super::TimerName::TimeLastDataPacketReceived);
+
+        my_tun.tick_marked_timers(timer_mask);
+
+        // Only those timers marked should be udpated
+        assert!(!my_tun.timers[TimerName::TimeLastDataPacketSent].is_zero());
+        assert!(my_tun.timers[TimerName::TimeLastDataPacketReceived].is_zero());
+
+        // Reset the timers
+        my_tun.timers[TimerName::TimeLastDataPacketSent] = SafeDuration::from_millis(0);
+
+        my_tun.update_timers(&mut [0]);
+
+        // Now the timers should not update
+        assert!(my_tun.timers[TimerName::TimeLastDataPacketSent].is_zero());
+        assert!(!my_tun.timers[TimerName::TimeLastDataPacketReceived].is_zero());
+    }
 }