News for G1a4 persons.
Before getting to your specific G1 subgroup, G1 in general today seems most common in Iran and the countries bordering it to the west. But G1 has spread out as far east as India, Siberia and China and west to western Europe. Late last year we learned from a study that there is pocket of G1 persons also in Armenia, similar to the G1 pocket of men found earlier in Kazakhstan. We only have limited information about these Armenian samples, but the Kazakh men have been in the G project and well tested. New studies also showed that G1 is otherwise rare in the Caucasus Mountains area north of Armenia. It is unknown if the new Armenian samples might fall within G1a or not.
Your sample in the G project has provided valuable information. It is only by seeing as many samples as possible that new subgroups can be identified.
 There are two types of G1a4 men. 
(1) Those confirmed as having the defining value of 8 at marker DYS494.
(2) Those only predicted to have DYS494=8.
If you are only predicted DYS494=8, your overall marker values strongly suggest you are part of this subgroup, but full confirmation is recommended by ordering DYS494.  It is quite inexpensive.  A waiver on this for Mr. Millls because his relative is already confirmed, and the mutation is much older than your specific family.
As mentioned in the general news section, if you are willing to better define your grouping, I will be glad to give individual recommendations and help. rayhbanks@cox.net.