In short: For accounts you own or are authorised to operate, give each account that matters one static address and change nothing afterwards. A platform that has watched an account sign in from one network for months can read a new network as a risk signal.
Account management here means operating accounts you own, or accounts you are contracted to run, from an address that does not change between sessions. A static ISP address is a single IP whose registration belongs to a named internet provider, reserved to you until your paid period ends. A rotating pool does the opposite: each request, or each short sticky window, leaves from a new address, which is exactly the change this job is trying to avoid.
Sign-in checks do read the network, and some platforms document how. Microsoft’s Entra ID Protection lists risk detections for sign-ins with properties unfamiliar to the user’s history, for sign-ins from geographically distant locations, and for sign-ins from anonymous IP addresses such as Tor or anonymous VPNs. Most platforms publish less, but the address is one of the few signals every sign-in carries. Where access is bound to an address, the binding is explicit: Google Cloud lets you restrict an API key to specific IP addresses, and a key restricted that way is refused from anywhere else. The page rests on documentation like this and on the way static and rotating addresses differ, not on measurements of any platform; the terms it quotes come from our Terms of Service, Refund Policy and Acceptable Use Policy.