9
Herko's advise is very good.
If you have domain1.com registered at registerX (your hosting company for example) and then domain2.com registered at registerY you can go to godaddy and transfer your domains to them. Then your domains will have only one registar (godaddy) where you can manage all the DNS aspects of your domain. This way you can switch from host to host very easy.
This is very good, because having problems with is your hosting company can be common.
Hope this helps you.
Have a nice day
By the way, doing things this way I've never wait more than 24 hours