diff --git a/tasmota/xdrv_29_deepsleep.ino b/tasmota/xdrv_29_deepsleep.ino
index dc7d76adc..9cfa1f070 100644
--- a/tasmota/xdrv_29_deepsleep.ino
+++ b/tasmota/xdrv_29_deepsleep.ino
@@ -112,10 +112,10 @@ void DeepSleepPrepare(void)
   // if more then 10% timeslip = 0 == non valid wakeup; maybe manual
   timeslip = (timeslip < -(int32_t)Settings->deepsleep) ? 0 : (timeslip > (int32_t)Settings->deepsleep) ? 0 : 1;
   if (timeslip) {
-    RtcSettings.deepsleep_slip = (Settings->deepsleep + RtcSettings.nextwakeup - LocalTime()) * RtcSettings.deepsleep_slip / tmax((Settings->deepsleep - (millis() / 1000)),5);
+    RtcSettings.nextwakeup += Settings->deepsleep;
+    RtcSettings.deepsleep_slip = (RtcSettings.nextwakeup - LocalTime()) * RtcSettings.deepsleep_slip / tmax((Settings->deepsleep - (millis() / 1000)),5);
     // Avoid crazy numbers. Again maximum 10% deviation.
     RtcSettings.deepsleep_slip = tmin(tmax(RtcSettings.deepsleep_slip, 9000), 11000);
-    RtcSettings.nextwakeup += Settings->deepsleep;
   }
 
   // It may happen that wakeup in just <5 seconds in future