Well, that leaves 6 challenger events (no Asian Open, no Lombardia, no US Classic or Autumn Classic since they never go) and just three are before the grand prix. Alina can't do Finlandia since it conflicts with Japan Open (Finlandia is 4-7 October and Japan Open is 6 October).
The three before the GP:
Ondrej Nepela (19-22 September)
Nebelhorn (26-29 September)
Finlandia (4-7 October)
If all 9 of the GP ladies want a challenger, then all of these spots are taken.
The other three challengers are:
Alpen Trophy (Austria) on 11-18 November
Tallinn Trophy (Estonia) on 26 November - 2 December
Golden Spin of Zagreb (Croatia) on 5-8 December
This would leave nine spots for the following:
Anna Tarusina, Anastasia Gubanova, Anastasia Gulyakova, Serafima Sakhanovich, Anna Pogorilaya (still a question mark), Valeria Mikhailova, Elizaveta Nugumanova, Alisa Fedichkina, and Alena Leonova (just an approximate list). All of these ladies could get one spot, since there are nine of them. If Pogorilaya isn't ready to compete, I would think her spot would go to Samodurova since she only has one GP.