Minimum hours for a BN2 Captain with Yogie (Loganair to those in the know
) was 2500hrs total time with no minimum twin hours. The reason for these hours was because it was a 'dual rated' job, Captain on both the BN2 & DHC6. I believe it might have changed, its a while since I was there. The hours were similiar for a Northern Isles posting although the above was for the more demanding Glasgow based air ambulance. However, do not underestimate the difference in the flying from your current job. It is a very demanding working environment and you have to be able to make crunch decisions quickly and peoples lives may depend on it. The aircraft are very well maintained but also very 'tired' which makes it interesting in icing conditions and the west coast of Scotland gets some of the worst icing conditions anywhere in the world. All that moist gulf stream air, check out your met books!
I have met many, many people over the years who started their careers on the Islander at Yogie and they all look back fondly on it, but would never return to it! Some guys in the company do stay forever, but most realise BN2 time has its limitations. If you can get into the left chair on the twotter it will help, but it is below 5700kg and not real multi crew so again severly limited, its turbine time, but not as we know it Jim... (in the proper airlines).
Your biggest hurdle will be getting the JAR licence, and once you get over that massive hurdle you will want more than Loganair can offer, its a very limited company, with management to match!
As a way into airline operations, SOP's etc, it might be worth it, but keep your options open. Good Luck.