Hi [mention:86e257cba32d453cb439211626e999df:e9ed411860ed4f2ba0265705b8793d05],
We've updated the page (https://docs.sophos.com/nsg/sophos-firewall/18.5/Help/en-us/webhelp/onlinehelp/AdministratorHelp/Network/DynamicDNS/NetworkDynamicDNSProviderAdd/index.html) and removed the note.
Thanks again for your feedback and for helping us improve our documentation!