Hi.

Until some time, we were able to whitelist BuyPass IPs in order to perform the HTTP ACME challenge.

We got the information from this page which was:

IPv4: 185.62.160.0/22

IPv6: 2a03:520::/29

We now see that requests are coming from dynamic sources owned by Amazon, so I'm wondering if this IP whitelisting is not longer possible or what would be the recommended action to whitelist the challenge for restricted environments using HTTP challenges.

Thanks