Device Farm Source IP Range -Validation of provided information

In reference to: https://aws.amazon.com/device-farm/faqs/, Q: Are devices able to communicate with other services or systems that are available on the Internet? The FAQ states that I should allow the IP range 54.244.50.32-54.244.50.63 (aka 54.244.50.32/27) on my firewall.

I am trying to demonstrate as a Proof of concept this capability as part of a proposal. From the AWS Device Farm, I am accessing a UK based public IP address from the mobile device's browser. I have confirmed that the URL is resolving to the correct public address. On my firewall I am seeing a block of requests for https traffic coming from 99.78.196.0/22 (https://ipinfo.io/AS16509/99.78.196.0/22). This range appears to registered by AWS. ( I also seeing, as you would expect, other nibbles at the public IP that are being blocked.)

This range is clearly different to the advertised range in the FAQ.

Question:

1. Is the advertised IP range in the FAQ still correct?
2. Where would I find definitive information on the IP range for the device farm?

I appreciate your time in responding.