First the plane has'nt even flown yet... Second numbers change all the time this early in the "development" stage... They get into testing ect, the Max takeoff weight may drop or go up... Look at the 717. Depending on the waranty you want the max landing and Takeoff changes... Maybe SkyWest told them they have to come in at the majical 86,000 lbs or the contract is void... Im sure both partys have alot of this figured out.. The MRJ90 is no more then a CRJ900.... Plus i Doubt the "smart" Alaska group would add 100 RJ's, thats equal to Alaska's mainline fleet in numbers.....