diff --git a/src/core/ddsi/src/ddsi_acknack.c b/src/core/ddsi/src/ddsi_acknack.c
index 8de59e038c..1b0a4c8dce 100644
--- a/src/core/ddsi/src/ddsi_acknack.c
+++ b/src/core/ddsi/src/ddsi_acknack.c
@@ -505,20 +505,15 @@ static struct ddsi_xmsg *make_and_resched_acknack (struct ddsi_xevent *ev, struc
 
 static dds_duration_t preemptive_acknack_interval (const struct ddsi_pwr_rd_match *rwn)
 {
-  if (rwn->t_last_ack.v < rwn->tcreate.v)
-    return 0;
+  const dds_duration_t age = rwn->t_last_ack.v - rwn->tcreate.v;
+  if (age <= DDS_SECS (10))
+    return DDS_SECS (1);
+  else if (age <= DDS_SECS (60))
+    return DDS_SECS (2);
+  else if (age <= DDS_SECS (120))
+    return DDS_SECS (5);
   else
-  {
-    const dds_duration_t age = rwn->t_last_ack.v - rwn->tcreate.v;
-    if (age <= DDS_SECS (10))
-      return DDS_SECS (1);
-    else if (age <= DDS_SECS (60))
-      return DDS_SECS (2);
-    else if (age <= DDS_SECS (120))
-      return DDS_SECS (5);
-    else
-      return DDS_SECS (10);
-  }
+    return DDS_SECS (10);
 }
 
 static struct ddsi_xmsg *make_preemptive_acknack (struct ddsi_xevent *ev, struct ddsi_proxy_writer *pwr, struct ddsi_pwr_rd_match *rwn, ddsrt_mtime_t tnow)
diff --git a/src/core/ddsi/src/ddsi_endpoint_match.c b/src/core/ddsi/src/ddsi_endpoint_match.c
index bbcf695c6d..f40a8ba84a 100644
--- a/src/core/ddsi/src/ddsi_endpoint_match.c
+++ b/src/core/ddsi/src/ddsi_endpoint_match.c
@@ -1026,7 +1026,7 @@ void ddsi_proxy_writer_add_connection (struct ddsi_proxy_writer *pwr, struct dds
   ELOGDISC (pwr, "  ddsi_proxy_writer_add_connection(pwr "PGUIDFMT" rd "PGUIDFMT")",
             PGUID (pwr->e.guid), PGUID (rd->e.guid));
   m->rd_guid = rd->e.guid;
-  m->tcreate = ddsrt_time_monotonic ();
+  m->tcreate = tnow;
 
   /* We track the last heartbeat count value per reader--proxy-writer
      pair, so that we can correctly handle directed heartbeats. The