diff --git a/test/tap/layouts-test.js b/test/tap/layouts-test.js
index 7ee6977..5ca75d6 100644
--- a/test/tap/layouts-test.js
+++ b/test/tap/layouts-test.js
@@ -262,7 +262,7 @@ test("log4js layouts", batch => {
     const columnNumber = 14;
     const event = {
       data: ["this is a test"],
-      startTime: new Date(Date.UTC(2010, 11, 5, 3, 18, 30, 45)),
+      startTime: new Date("2010-12-05 14:18:30.045"),
       categoryName: "multiple.levels.of.tests",
       level: {
         toString() {
@@ -279,8 +279,6 @@ test("log4js layouts", batch => {
       columnNumber
     };
 
-    event.startTime.getTimezoneOffset = () => -600;
-
     const layout = require("../../lib/layouts").patternLayout;
 
     t.test('should default to "time logLevel loggerName - message"', assert => {
@@ -411,6 +409,8 @@ test("log4js layouts", batch => {
         "%d{ISO8601}",
         "2010-12-05T14:18:30.045"
       );
+
+      event.startTime.getTimezoneOffset = () => -600;
       testPattern(
         assert,
         layout,
@@ -419,6 +419,8 @@ test("log4js layouts", batch => {
         "%d{ISO8601_WITH_TZ_OFFSET}",
         "2010-12-05T03:18:30.045+1000"
       );
+      delete event.startTime.getTimezoneOffset;
+
       testPattern(
         assert,
         layout,