It doesn't have to be *all* that far to the pole--it's just less common the farther away you go. (Actually, I think it's less common close to the poles than it is in a band surrounding it. See, e.g.,
http://www.swpc.noaa.gov/products/aurora-30-minute-forecast -- it's over the northern portions of the British isles.)
Assuming-- and it's a big assumption-- that the Spires were built on a version of Earth, then they are limited to current/near-future landmasses. (Near future in geologic terms-- no new supercontinents, etc.) If Albion is indeed built in somewhere in England, then Aurora could be as close as northern Scotland-- to get regular visitations from its namesake) or much, much farther away.
Since Spire Aurora doesn't seem to be visible from the top of Spire Albion (which is above the mists), we can find a minimum distance between the two-- The horizon is ~125 miles away from two miles up (which is, I believe the approximate height of Albion. And we know that ships can go up to 7-8 miles, given a powerful enough lift crystal and breathing apparatus for the crew, which would broaden the range to ~250 miles. (Of course, that's to the base of Spire Aurora-- since it, too, probably protrudes from the mists, the minimum distance is actually farther, but not by much.)