code: public static TimestampBound ofMinReadTimestamp(Timestamp timestamp) {
      return new TimestampBound(Mode.MIN_READ_TIMESTAMP, checkNotNull(timestamp), null);
    }
docs: Returns a timestamp bound that will perform reads and queries at a timestamp chosen to be at
  least {@code timestamp}. This is useful for requesting fresher data than some previous read, or
  data that is fresh enough to observe the effects of some previously committed transaction whose
  timestamp is known.
  
  <p>Note that this option can only be used in single-use reads and single-use read-only
  transactions.