Forend fit for pistol barrels

[Blackhawker]

I realize that a single screw barrel can use a two screw forend, as described in the FAQ's but does this apply to T/C custom shop barrels as well?  For example, Ed's Contenders advertises a 12 inch bull barrel with one dovetail.  If this is a custom shop barrel is the dovetail located in a different area as opposed to standard barrels?

[Bullseye]

The only custom shop barrel I have ever purchased was a 10" and it came with two dovetail screws spaced for a 14" barrel forearm.  That was standard, I did not specify it.  I do not know if they are all like that or not.