Many thanks to everyone!
Owl: 3 suites still left
Glen, nice to see you here, too. Yes, the 7th is A. The whole tuning is first six strings normal with drop-D, 7th=low A, 8th=low G, 9th=low B and 10th=re-entrant G, same as 6th@3rd fret with in standard. The Fugue needs the low G four times, that's why it's there. Also, as you said, the 7th=A is handy for fretting, in fact the low basses of Allegro are all played on 7th. Some nasty stretches there, but that's much better than trying to stop the ringing open bass notes in that speed.