Hey! Very exciting that you’re testing out the async endpoint already.
From our Analytics Overview page:
asynchronous analytics queries are subject to the following limits:
A maximum of 100 concurrent (queued or processing) asynchronous job queries are permitted per advertiser account
Result files expire 48 hours after the job is successful and the URL is returned
Queries taking over 60 minutes to process with automatically time out.
So you should be able to run other asynchronous stats jobs in parallel with this processing one, and it will not block the others, and should eventually either succeed or time out. However, it would be great if you could provide the advertiser account ID for this stuck job, that would help us further investigate the issue.