Can a pipeline step with a concurrency-group run a pipeline with a manual trigger?

[Stefan Fußenegger]

Given this bitbucket-pipelines.yml with a `default` pipeline with `concurrency-group`, `condition: state: ...`, and `type: pipelines` with `trigger: manual` in the child pipeline:

What is the expected behavior for concurrent builds hitting the `trigger: manual`? Assuming #1 is waiting at the trigger, is #2

1. waiting for the `concurrency-group: production` lock or
2. proceeding into the child pipeline and #1 can no longer be run?

If it's 1), is there a way to release the lock without running the manual step?