Going on a tangent, if they were to get 2 or 3 787s or 350s, that are aerodynamically fuel saving, it could work out better in the long run, though the cost of buying or leasing it will be prohibitive in the first few years of operations with them, but in the end, they would save fuel cost.
Yes, they would have to train their pilots to fly the 787s or the 350s, but flying those aircrafts will have a lower running cost.
Their 737-800s would be past the first quarter stage of their flying lives, maybe 10 to 15 years to go.
Their 3rd hand F100 take a lot of wear and tear, seeing it was from Skywest, who did a lot of flying out in the sticks, and they were used to be fifo, so they would have had a lot of strain, many touch downs and take offs, probably more than their 737s.