Having a bit of trouble working out how to setup the dialling rules with A@H

If I have the following in the Outbound Routing -> VoIPBuster section
*006|.
and calls prefixed with *006 are routed via VoIPBuster 9I do however have to
use the full international number, which is a pain)

I want to be able to just dial numbers without prefixing, and not having to
add 0044 to the beginning.

What do I need to add to the Dial Pattern so this will work, for 020 for
example?
(I managed to set it all up with a different asterisk package, but I am
unsure how I am supposed to do it with A@H!)

Ta!

Sparks...