diff --git a/src/options.c b/src/options.c
index bc8d010..6613fbd 100644
--- a/src/options.c
+++ b/src/options.c
@@ -157,10 +157,6 @@ enum timestamp_t timestamp_option_parse(const char *arg)
         {
             return TIMESTAMP_ISO8601;
         }
-        else
-        {
-            warning_printf("Unknown timestamp type, falling back to '24hour' default format");
-        }
     }
 
     return timestamp;