Would this "industry source" be that idiot Les Bloxham? I don't think I have heard one accurate word escape his mouth on anything concerning aviation.
The ONLY benefit in getting the 340B over the Q300/ATR42 is reduced training costs, which would only be a one off saving due to the fact that whichever new aircraft (Q300/ATR) they aquire will come with a simulator so no more sending crews to Melbourne. The Dash and ATR would be cheaper to run thanks to their more efficient engines and substantially lower maintenance costs. This would far outweigh any benefits in reduced training costs. The 33 seat limit of the saab is starting to cost the company money in lost revenue due to the fact that flights are booked out and the pax are looking elsewhere for flights.
The fact that the figure of 180 million is being used says to me that they are going to be purchasing a new fleet and using the sale of the saabs they own to offset the aquisition costs.