diff --git a/reactor.py b/reactor.py
index 92b5e5d..7c117cc 100644
--- a/reactor.py
+++ b/reactor.py
@@ -34,7 +34,8 @@ class Glimpse():
             if self.activated_num == 0:
                 return
             self.avg_efactor = round(self.avg_efactor / self.activated_num, 2)
-        self.next_date = -1
+        if self.next_date == 0x3f3f3f3f:
+            self.next_date = -1
         return
 
 class Apparatus():