public com.google.protobuf.TimestampOrBuilder getRecommendedNextDiffOrBuilder() {
      if (recommendedNextDiffBuilder_ != null) {
        return recommendedNextDiffBuilder_.getMessageOrBuilder();
      } else {
        return recommendedNextDiff_ == null
            ? com.google.protobuf.Timestamp.getDefaultInstance()
            : recommendedNextDiff_;
      }
    }
<pre>
The soonest the client should wait before issuing any diff
request. Querying sooner is unlikely to produce a meaningful diff.
Waiting longer is acceptable considering the use case.
If this field is not set clients may update as soon as they want.
</pre>

<code>.google.protobuf.Timestamp recommended_next_diff = 2;</code>
java-webrisk/proto-google-cloud-webrisk-v1beta1/src/main/java/com/google/webrisk/v1beta1/ComputeThreatListDiffResponse.java