re: nameservers, it depends, most newer systems have it updating within about 4 hours, that being said, some ISP's DNS cached can be borked, so it can take up t

re: nameservers, it depends, most newer systems have it updating within about 4 hours, that being said, some ISP's DNS cached can be borked, so it can take up to 24-48 hours. You should really leave up your old site in parallel with the new one while you're moving it, I'd say go for a period of 7 days just to be on the safe side. Hope this helps your needs.