Remember that gate assignments are not the same every day, so don't get too focused on specific gates.

A to Z transfers are quick and painless, even if A30 to Z66 is not far from the longest possible such connection. It's a bit of a walk, but even with that they should easily make it. Basically they just walk down the old A pier from A30 (or whatever gate OU actually arrives on), pass passport control near gate A13 before taking their stairs or escalators up and walk to Z66 (or any other of the Z50-66 gates usually used by LH for US-bound departures).