reactor-core/src/main/java/reactor/core/publisher/Flux.java
public final Flux<T> timeout(Duration timeout, @Nullable Publisher<? extends T> fallback) {
		return timeout(timeout, fallback, Schedulers.parallel());
	}
public final Flux<T> timeout(Duration timeout, @Nullable Publisher<? extends T> fallback) {
		return timeout(timeout, fallback, Schedulers.parallel());
	}
Switch to a fallback {@link Flux} as soon as no item is emitted within the
given {@link Duration} from the previous emission (or the subscription for the first item).
<p>
If the given {@link Publisher} is null, signal a {@link TimeoutException} instead.

<p>
<img class="marble" src="doc-files/marbles/timeoutFallbackForFlux.svg" alt="">

@param timeout the timeout between two signals from this {@link Flux}
@param fallback the fallback {@link Publisher} to subscribe when a timeout occurs

@return a {@link Flux} that will fallback to a different {@link Publisher} in case of a per-item timeout