Fleet replacement
Although I agree the ATR42 is a good replacement, the 48/50 seater capacity may not be completely filled by passengers, thus a 30 seater would probably be more economical? I suggest that they purchase new Embraer 120 Brasilia's which are still in production if the need arises, they are pretty sturdy aircraft and proven domestic aircraft which would be similar to the current Saab 340 fleet. Another option is the new Viking DHC-5NG Buffalo utility aircraft that have a capacity of 30-40 and are versatile for cargo operations too, not to mention the extraordinary short field performance. Another option for smaller aircraft could be the new 19 seater Cessna 408 SkyCourier for routes to say Campbeltown, Tiree, Benbecula etc?