Yes I think I have found some logic (too much free time). Though it does not matter as you are always in 'South'position. The first pair to register are N/S Second pair to register are E/W 3rd, 5th etc are N/S. Of course Entries are displayed in alphabetical order. After that the 'inviter' becomes W, 'invited' is E. Similar for N/S (I think!) Hav'nt worked out how pairs are assigned to a table at the start but after that normal Mitchel applies. I always reply to queries that 'BBO decides', after all it does not matter.