I replied to your post elsewhere, but FYI at the moment everything is built around the system listed in the wiki and the current practice is based around the construction and access to the road (if it has ramps, number of lanes etc) but as I understand it, that doesn't match the DoT classifications (as seen on OS based mapping like Bing's) and those will become standard after the map import.

The naming convention should be:-
Number (Direction) Hyphen Name
A12 (W) - Eastern Avenue
A720 (E) - The City of Edinburgh Bypass

but I've noticed that there is little consistency across the UK map at this moment in time so you might want to concentrate on getting new roads in, named & connected properly then wait & see what the basemap update brings before looking at doing corrections...