Index: tests/phpunit/testcases/core/functions.php
===================================================================
--- tests/phpunit/testcases/core/functions.php
+++ tests/phpunit/testcases/core/functions.php
@@ -612,6 +612,64 @@
 	}
 
 	/**
+	 * @group strtotime
+	 */
+	public function test_strtotime_server_timezone_different_than_utc() {
+		// Pretend that this is a UTC date.
+		$utc_date = '2008-03-25 17:13:55';
+
+		// backup timezone
+		$tz_backup = date_default_timezone_get();
+
+		// Pretend server has set timezone to Paris.
+		date_default_timezone_set( 'Europe/Paris' );
+
+		$paris_timestamp = strtotime( $utc_date );
+
+		// Set timezone back to UTC.
+		date_default_timezone_set( 'UTC' );
+
+		$utc_timestamp = strtotime( $utc_date );
+
+		// revert timezone back to normal
+		if ( $tz_backup ) {
+			date_default_timezone_set( $tz_backup );
+		}
+
+		// Assert that convert Paris time doesn't match original UTC timestamp.
+		$this->assertNotSame( $paris_timestamp, $utc_timestamp );
+	}
+
+	/**
+	 * @group strtotime
+	 */
+	public function test_strtotime_server_timezone_different_but_using_mysql2date_instead_of_strtotime() {
+		// Pretend that this is a UTC date.
+		$utc_date = '2008-03-25 17:13:55';
+
+		// backup timezone
+		$tz_backup = date_default_timezone_get();
+
+		// Pretend server has set timezone to Paris.
+		date_default_timezone_set( 'Europe/Paris' );
+
+		$mysql2date = mysql2date( 'G', $utc_date );
+
+		// Set timezone to UTC.
+		date_default_timezone_set( 'UTC' );
+
+		$utc_timestamp = strtotime( $utc_date );
+
+		// revert timezone back to normal
+		if ( $tz_backup ) {
+			date_default_timezone_set( $tz_backup );
+		}
+
+		// Assert same even though server timezone is different.
+		$this->assertSame( $mysql2date, $utc_timestamp );
+	}
+
+	/**
 	 * @group bp_attachments
 	 * @group bp_upload_dir
 	 */