The fleet shares would not change. The TAC is the total allowable catch, which is the quantum of fish that can come out of the water. The fleet shares are how that quantum is divided among the different interests in the fishery.
Evidence of meeting #100 for Fisheries and Oceans in the 44th Parliament, 1st Session. (The original version is on Parliament’s site, as are the minutes.) The winning word was fishery.
A recording is available from Parliament.