WebFlux + APM Agent 1.55: Incorrect Transaction Duration

I'm using the Elastic APM Java agent version 1.55.0 in a Java Reactive (WebFlux) application. I'm instrumenting my code using annotations like @CaptureTransaction and @CaptureSpan.

The problem is that all the transactions and spans show unrealistically short durations (e.g., 196 μs), even though the actual processing takes much longer.

It seems like the agent is measuring the duration only until the Publisher is returned, not until it's subscribed and completed. This results in incomplete or inaccurate traces and metrics.

Is this a known limitation in version 1.55?
Is there a recommended workaround (e.g., manual instrumentation using ElasticApm.startTransaction()), or is this expected to be fixed in a later release?