The agreement is due to take effect on September 1 and will apparently see the carrier abandon its current short-range regional route network flown by Saab 340's in favor of becoming a pure codeshare operation. Sol's current fleet of four 34-seat turboprop Saab 340's, two "A" and two "B" models, are designed for short to medium range flights of up to about 400 miles / 650 km and are not suitable to operate on the longer-distance legs flown by the longer-range and greater capacity jets flown by AR /AU so Sol will reportedly replace its Saabs with six 50-seat CRJ-200 regional jets from Spanish regional carrier Air Nostrum with the first airframe due to arrive in early October, the second in November, two more in January, and the last two in March 2016. Air Nostrum currently has a fleet of 44 aircraft; 5 ATR-72-600's, 3 CRJ-100's, 15 CRJ-200's (seven of which are in storage), 11 CRJ-900's and 10 CRJ-1000's and is looking to dispose of its CRJ-200's in favor of more CRJ-900's.
The agreement between Sol and Air Nostrum is reportedly a lease with an option to buy and includes technical support from the Spanish carrier. Sol flight crews are said to be already undergoing simulator training with flight dispatchers to start training soon too.