For software that opens dozens of threads at once, addresses from open lists fail on the first requests. An IPv4 pool with rotation keeps the load steady. For tasks like these, it makes sense to take a rotating pool with spare threads. Details: https://telegra.ph/HTTP-Proxy-Service-11-10 Plans cover 1,000, 3,000 and 5,000 threads. There is a free test of up to 2 hours before you pay. For Private IPv4 proxy the pool runs from the first launch.