Here’s a pointer for website hosts transferring their domains over. About a day before your migration you want to drop your TTL values. This forces faster DNS lookups – the reason you have to wait this long is because DNS cache’s store the amount of time to check this again as a way of reducing the load on your DNS server (and nobody likes to see their DNS server fall over).

; zone 'zonename.com' 
$TTL 86400 @ IN SOA ns1.zonename.com. host.zonename.com. 
( 2006052101 ; Serial 
10800 ; Refresh 3 hours 
3600 ; Retry 1 hour 
604800 ; Expire 1 week 
86400 ); Minimum 24 hours 

If you knock that TTL value in bold down to 60 then you’ll be looking at 60 seconds before it goes live. But remember, you’ll need to wait the time you’ve already specified (86400 / 24 hours in this case) before you tell your registrar the new nameservers to avoid messing things up for your clients.

Hope you find this useful!