If it ever got to that point, they'd probably just move one of the data centers, either Ather or Primal, back to the East Coast, or in the very least a central location like Dallas.
Although that's probably what they should have done in the first place. Blizzard has kept four separate Data centers across the U.S. (L.A., Chicago, Dallas, and New York, I believe) to cover the entire country for years. Seems kind of silly to move both data centers to the same location.