According to https://scihub.copernicus.eu/userguide/LongTermArchive
A user quota on the maximum number of requests per hour per user is
set. Products restored from the long term archives are kept online for a
period of at least 3 days. Quota and keeping time will be fine tuned
according to the usage patterns to ensure efficient access to the most
recent and frequently downloaded data.
The OData API returns an HTTP status code 202 Accepted when a
request is successfully submitted to the LTA.
The same code is provided also in case of product already requested by
Did you try to make multiple requests? I have never used LTA products in bulk, but I would guess that it is not up to us to choose how many requests you can make.
If you just keep a script running (or schedule it) to make the requests and download in parallel (by using threading), I think this could save you much time