What is it with you and Scotland? If Scotland was relying on BP to give it it's money then so would the Shetlands. I have never heard of anyone making contracts where they only get money for resources if it is the choice of the person they have sold it to but I have no interest in Scotland makings its money through oil.
It is through renewables, hydrogen, offshore wind power, tidal energy and wave energy that Scotland will be able to make a large section of its money.
You it would appear are far more interested in Shetland leaving Scotland than Shetland.
Scotland will not be able to make the money off any of those things without foreign investment--something it will have very little of without oil and natural gas. You would appear as if you are far more interested in Scotland leaving the UK than the Scotish people's ability to have a self-sufficient country.