Response times will vary depending on the publisher. While there may be occasions that you receive a licence almost instantly, sometimes a permission request may take some time to process. For this reason, we do advise allowing 6-8 weeks before your deadline to account for longer processing times.
If you have not received a response within a reasonable amount of time, you can follow up with the publisher by leaving a comment on the request. This will highlight the request and send it to the top of the publisher's Request Manager inbox for review.