Cloudflare has asked me to change nameserver to be able to administrate DNS settings from within my own Cloudflare login (which I made recently), even though the domain already has Cloudflare nameservers.
This web page basically seems to tell me that as long as DNSSEC is switched off at my domain host then I can change to the new Cloudflare nameservers supplied to me by Cloudflare and 24 hours later I should gain access: https://developers.cloudflare.com/dns/zone-setups/full-setup/setup#step3
Are you able to advise me on this and how to prevent disruption to website and email hosting?
In practice the switch should be almost immediate. Iād note your DNS settings at your host before switching the nameservers to ensure everything is correct in your CF DNS dashboard. Any website downtime should be minimal (if possible, do the switch during the lowest traffic hours). Email is fairly forgiving when a server is temporarily unavailable, and the sending email server will usually retry delivering several more times over a day or so until it gives up.
If the domain is already on Cloudflare, it is likely better for the existing person managing the domain to invite you to that account as opposed to changing the nameservers.