public Builder clearValidAfterDuration() {
        if (validAfterDurationBuilder_ == null) {
          if (startTimingConstraintsCase_ == 3) {
            startTimingConstraintsCase_ = 0;
            startTimingConstraints_ = null;
            onChanged();
          }
        } else {
          if (startTimingConstraintsCase_ == 3) {
            startTimingConstraintsCase_ = 0;
            startTimingConstraints_ = null;
          }
          validAfterDurationBuilder_.clear();
        }
        return this;
      }
<pre>
Optional. A relative time after which resources may be created.
</pre>

<code>
.google.protobuf.Duration valid_after_duration = 3 [(.google.api.field_behavior) = OPTIONAL];
</code>
java-tpu/proto-google-cloud-tpu-v2/src/main/java/com/google/cloud/tpu/v2/QueuedResource.java