It seems they will use the current series format (1A/2nd best 3rd, 2B/2C, 1C/2A, 1B/best 3rd) but I hope there will be no draw, only a serpentine assignment. If not this is completely flawed as only the first pot seeds are assigned a group, the rest being randomly drawn. This means you can be the 4th seed and still end up with the 1st, finish second in the group and have to face the group C winner (3rd seed) in QF.
The seeding is also to be determined. Using Madrid results could completely shake up the face of the tournament depending on how it goes (same for Challenger teams).
Anyway, should it be done now, with South Africa taking the last spot we would have :
A :
B :
C :