I have just changed the DNS A-Record with my ISP to point to the IP address of our new web hosting server (which takes up to "24 - 48hrs" to propagate around the world).
In my experience, it "usually" takes about 3 - 4 hours for us to check and see the site on the Internet via a local web browser however, if we check within our LAN, this time frame can be distorted by a greater length of time as cached record is returned from our local DNS server returning the old site.
How can I force our local DNS server to re-check the master DNS record with our ISP? Or get it to re-check at a more frequent time frame e.g. an hour (once the new site is seen, I can then revert it back to lessen the network traffic).
Apologies for the lack of official terminology!