Korbes's injury was from the last rep of last season, and she spoke about it last fall in a long interview on the Ballet Initiative podcast. I'm sure when Boal scheduled "The Sleeping Beauty" last spring, Korbes was one of his choices for Aurora, but they wouldn't have started rehearsals last season, and Biasucci couldn't have been her understudy.
Biasucci joined PNB in 2011. In her second rep, she danced "Divertimento from 'Baiser de la fee'" and Little Red Riding Hood in the "Sleeping Beauty" Wedding Act in the "Love Stories" program (Nov 2011). Korbes was cast in "Afternoon of a Faun" and "Romeo et Juliette PDD," with Chapman, Ricard Orza, and Rausch dancing Aurora, but Korbes withdrew first from weekend one, and then, finally from week two, and missed the rep. If Biasucci understudied Aurora at the time, not a given with everything else she was doing, which might have included learning multiple corps roles from scratch in "Nutcracker"by then, she didn't dance it. I don't think PNB has understudies or fourth/fifth casts for specific Principals: if she were understudying Aurora, it would have been for all other casts, and often, the understudies/last casts for full-lengths, at least, are in separate partnerships.
I'm looking forward to seeing Rausch and Cruz together: they both have such long lines. With Chapman doing a run of Queens, and Ricard Orza dancing Lilac, the other Auroras are on the short side -- Nakamura, Foster, Biasucci -- and would look out-of-proportion with Cruz. I'm glad to see Rausch and Bold with other partners, too, because he tends to focus on partnering her and lose his own character, and I think he and Foster could have a great dynamic together, as well as having good proportions.
I don't know what would have happened had Chapman, a radiant Aurora in "Love Stories," and Korbes been able to do the role. If he had five casts, that would mean one cast with one performance, which is rare to assign to a Principal. I suspect there would have been four casts, with Biasucci an understudy in this round. She was given great opportunities up front her first season, but she also understudied a number of roles that year and ended up being featured in every, or almost every rep that year. She's been given wonderful opportunities since, but in some reps last season, hadn't been cast prominently. I'm glad she's being featured again.