Customers who host their websites with AfterOffice but run their DNS nameservers (NS) elsewhere can do so by configuring IP pointing to our web server.
However, please be informed that it is our policy to host the DNS of our web-hosting customers.
This is due to we have the flexibility to change the IP / server when required.
It is not a good practice and we do not encourage customers to switch away their DNS hosting while pointing the server back on us, as your website may be down if you could not follow up with the changes.
Hope you can understand that it is not possible for us to always inform the customers on the changes done on each server upgrade and during emergency cases.
We suggest you to host the DNS with AfterOffice, to eliminate the issues as stated above.