Monitor DNS changes.
During the time of transition,Â it's important to monitor the progress of the DNS update. This can be done very easily using a free tool such as HyperTrace. HyperTrace can be downloaded here:
HyperTrace shows you the route that information travels from your machine to another machine on the internet. It will show you the Name Server of your current hosting service and once the update starts occurring, the new hosting service. Bear in mind that this may "bounce" from old to new during 72 hour transition window and it may be a day or two before you see the new nameserver details at all.