I think the minimum loan amount has increased to 2K, so...
AA 10 + -50 = -40
A-B 60 + -50 = 10
C-E 90 + -50 = 40
Only the AA borrowers will see a return for origination. And since you must make interest payments
Returning AA borrowers, one year term (6.65%) = 21.88
First-time AA borrowers, one year term (7.00%) = 23.04
-40 + 21.88 = 28.12 NET -or-
-40 + 23.04 = 26.96 NET