I use a hosting companies name servers for a lot of my domains but to mask this I point sub domains of my own domain to my hosts name servers IPs.
So I have created ns1.mydomain.com and I point it to 123.456.789.111. Then I update the domains name servers to point to ns1.mydomain.com.
I have recently had to change the IP addresses for these name servers as I have moved hosts.
The problem is that when I do a whois lookup it lists the name servers correctly but shows the old IP addresses (the ones that point to the old host).
But if I ping ns1.mydomain.com it shows the correct IP address so it must have propagated already.
Am I doing something wrong?