diff --git a/include/timesync.h b/include/timesync.h
index 82da84f7..8b8c42bc 100644
--- a/include/timesync.h
+++ b/include/timesync.h
@@ -12,7 +12,9 @@
 
 void timesync_init(void);
 void send_timesync_req(void);
-int recv_timesync_ans(const uint8_t seq_no, const uint8_t buf[], const uint8_t buf_len);
+
+int recv_timesync_ans(const uint8_t buf[], uint8_t buf_len);
+
 void process_timesync_req(void *taskparameter);
 void store_time_sync_req(uint32_t t_millisec);
 
diff --git a/src/lorawan.cpp b/src/lorawan.cpp
index 088d4305..e6aa7114 100644
--- a/src/lorawan.cpp
+++ b/src/lorawan.cpp
@@ -561,8 +561,8 @@ void myRxCallback(void *pUserData, uint8_t port, const uint8_t *pMsg,
 
 #if (TIME_SYNC_LORASERVER)
     // valid timesync answer -> call timesync processor
-    if ((port >= TIMEANSWERPORT_MIN) && (port <= TIMEANSWERPORT_MAX)) {
-      recv_timesync_ans(port, pMsg, nMsg);
+    if (port == TIMEPORT) {
+      recv_timesync_ans(pMsg, nMsg);
       break;
     }
 #endif
diff --git a/src/paxcounter.conf b/src/paxcounter.conf
index 40852f59..f7826a9a 100644
--- a/src/paxcounter.conf
+++ b/src/paxcounter.conf
@@ -30,7 +30,7 @@
 * |< Scan Window >       |< Scan Window >       | ... |< Scan Window >       |
 * |<    Scan Interval   >|<    Scan Interval   >| ... |<    Scan Interval   >|
 * |<                   Scan duration                                        >|
-* 
+*
 * Scan duration sets how long scanning should be going on, before starting a new scan cycle. 0 means infinite (default).
 * Scan window sets how much of the interval should be occupied by scanning. Should be >= BLESCANINTERVAL.
 * Scan interval is how long scanning should be done on each channel. BLE uses 3 channels for advertising.
@@ -97,9 +97,9 @@
 #define BEACONPORT                      6       // beacon alarms
 #define BMEPORT                         7       // BME680 sensor
 #define BATTPORT                        8       // battery voltage
-#define TIMEPORT                        9       // time query
-#define TIMEANSWERPORT_MIN              0xA0    // time answer, start of port range
-#define TIMEANSWERPORT_MAX              0xDF    // time answer, end of port range
+#define TIMEPORT                        9       // time query and response
+#define TIMEDIFFPORT                    13      // time adjust diff
+#define TIMEREQUEST_MAX_SEQNO          250    // time answer, start of port range
 #define SENSOR1PORT                     10      // user sensor #1
 #define SENSOR2PORT                     11      // user sensor #2
 #define SENSOR3PORT                     12      // user sensor #3
diff --git a/src/timesync.cpp b/src/timesync.cpp
index 6c60a225..a50d7ca1 100644
--- a/src/timesync.cpp
+++ b/src/timesync.cpp
@@ -25,7 +25,7 @@ typedef std::chrono::duration<long long int, std::ratio<1, 1000>>
 
 TaskHandle_t timeSyncReqTask = NULL;
 
-static uint8_t time_sync_seqNo = random(TIMEANSWERPORT_MIN, TIMEANSWERPORT_MAX);
+static uint8_t time_sync_seqNo = 0;
 static bool timeSyncPending = false;
 static myClock_timepoint time_sync_tx[TIME_SYNC_SAMPLES];
 static myClock_timepoint time_sync_rx[TIME_SYNC_SAMPLES];
@@ -93,9 +93,10 @@ void process_timesync_req(void *taskparameter) {
                         time_point_cast<milliseconds>(time_sync_tx[k]);
 
       // wrap around seqNo, keeping it in time port range
-      time_sync_seqNo = (time_sync_seqNo < TIMEANSWERPORT_MAX)
-                            ? time_sync_seqNo + 1
-                            : TIMEANSWERPORT_MIN;
+      time_sync_seqNo++;
+      if(time_sync_seqNo > TIMEREQUEST_MAX_SEQNO) {
+        time_sync_seqNo = 0;
+      }
 
       if (i < TIME_SYNC_SAMPLES - 1) {
         // wait until next cycle
@@ -154,7 +155,9 @@ void store_time_sync_req(uint32_t timestamp) {
 }
 
 // process timeserver timestamp answer, called from lorawan.cpp
-int recv_timesync_ans(const uint8_t seq_no, const uint8_t buf[], const uint8_t buf_len) {
+int recv_timesync_ans(const uint8_t buf[], const uint8_t buf_len) {
+  uint8_t seq_no = buf[0];
+  buf++;
 
   // if no timesync handshake is pending then exit
   if (!timeSyncPending)
@@ -223,4 +226,4 @@ void timesync_init() {
                           1);                   // CPU core
 }
 
-#endif
\ No newline at end of file
+#endif