Alright, got some great news from a buddy working at Airbus. All 4 Airbuses are confirmed for Spirit Airlines. Here are the official delivery dates:

msn 4206 to be delivered on 4th of March.
msn 4264 to be delivered on 9th of April
msn 4321 to be delivered on 28th of May
msn 4431 to be delivered on 8th of September