Keep a list of where your static IP is configured: (or use a public DNS record where allowed, but security/propagation and small changes can break things)
DNS A records
Kamar Portal/Whitelist
Test Kamar Directory Services to make sure 3rd parties accept the new IP etc
Google/M365 Trusted locations & conditional access policies
NZ Herald (if you want the premium articles)
Adobe Shared / Wheelers / Ancestry / Epic
Britannica
etc as you've mentioned Vern
Outside of that any VoIP/CCTV that isn't using DNS on clients devices etc
Matt