problem fetching AAS Journals PDFs

[trentdupuy]

I waited several days to do a test to see how many PDFs I could fetch in a row from AAS Journals. I was able to execute 3 individual command-line fetches, and on the 4th fetch I got the error

Fetching PDF file from Journal website:
Request succeeded, but fetched content is not a PDF (might have been
redirected to website due to paywall).
Fetching PDF file from ADS website:
Request failed with status code 404: NOT FOUND

I then went to ADS and clicked through to try to download the same from the "IOP PDF" link. I was taken to a human test, which I passed. I re-ran the same fetch command, and it succeeded.

On the next (5th PDF) fetch, I got the same error as above. I think went to ADS again, clicked on IOP PDF, and my browser took me directly to the PDF.

So the result of the test seems to be you can download 3-4 PDFs before the AAS Journals lock you out for some period of time. I have not run into this problem with MNRAS or A&A.