How the UK government can assert that fishing rights are one of the two main priorities is totally incredulous given that decades of mismanagement by successive British governments have hastened the decline of an already threatened industry before the UK even joined the EU.
The quota hoppers ( ie. Spanish Trawlers registered under a British flag) that joined the biggest English fleet in a cooperative pre 1970's was the beginning of decline. Then followed a UN convention which allowed a coastal state to extend its fishing zone to 200 miles.
By the mid 1970's Iceland seized upon the opportunity given by the 1970 UN convention and launched the cod wars to seize more fish in British and Irish territorial waters. The British government did nothing and compensated whole fleets to stay in port doing nothing.
Next came the Belgian & Dutch fleets who poached sole in the Irish Sea but again the British government didn't advise the UK fleets that this would affect their future quotas as it was later based on the size of catches historically made during this much earlier period.
As the number of fishing trawlers that were actually British owned shrank rather than just foreign owned but UK registered, the fishermen were abandoned and left out of work and forced to work in the gas and oil industry.