LocalDate inconsistency

I am trying to produce a Date object (java.util.Date) from a LocalDate object (java.time.LocalDate) in which I have the following criteria:

• Allow a parameter that can subtract a certain number of days from the Date object
• Have the Date & Time be the date and time currently in UTC
• Have the time at the beginning of the day i.e. 00:00:00
• The Timezone stamp (i.e. CDT or UTC) is irrelevant as I remove that from the String

To meet this criteria, I have created a test program, however I am getting interesting results when I modify a certain property of the LocalDate. See code below:

  public static void main (String args[]) {
    Long processingDaysInPast = 0L;
    LocalDate createdDate1 = LocalDate.now(Clock.systemUTC()).minusDays(processingDaysInPast);
    LocalDate createdDate2 = LocalDate.now(Clock.systemUTC()).minusDays(processingDaysInPast);
    System.out.println(createdDate1);
    System.out.println(createdDate1.atStartOfDay().toInstant(ZoneOffset.UTC));
    System.out.println(Date.from(createdDate1.atStartOfDay().toInstant(ZoneOffset.UTC)));
    System.out.println((createdDate2.atStartOfDay().atZone(ZoneId.systemDefault()).toInstant()));
    System.out.println(Date.from(createdDate2.atStartOfDay().atZone(ZoneId.systemDefault()).toInstant()));
}

Output:

 2017-08-14
 2017-08-14T00:00:00Z
 Sun Aug 13 19:00:00 CDT 2017
 2017-08-14
 2017-08-14T05:00:00Z
 Mon Aug 14 00:00:00 CDT 2017

When I add the value Date.from(createdDate1.atStartOfDay().toInstant(ZoneOffset.UTC)) I get the expected output of the date, with a 00:00:00 time field. However, if I do not add this parameter, such as: Date.from(createdDate2.atStartOfDay().atZone(ZoneId.systemDefault()).toInstant()) I get the resulting day before , at 19:00:00 why is this?

My main goal from this is to be able to capture a Date object, with the current UTC Date, and the Time zeroed out (StartOfDay).