public com.google.type.TimeOfDay.Builder getStartTimeBuilder() {
      bitField0_ |= 0x00000002;
      onChanged();
      return getStartTimeFieldBuilder().getBuilder();
    }
<pre>
Optional. Start time of the window in UTC.
</pre>

<code>.google.type.TimeOfDay start_time = 2 [(.google.api.field_behavior) = OPTIONAL];</code>
java-valkey/proto-google-cloud-valkey-v1/src/main/java/com/google/cloud/memorystore/v1/WeeklyMaintenanceWindow.java