have control of any issue of fishing licences for them,?and for how long those licences will be valid
Once we have the control we can issue licences to maximise/control the amount of fishing, but allowing it to continue while we get our own fishing fleet back to its previous size (in line with our new fishing area). At which time, time limited licences (to businesses in other countries) will expire to be replaced by increased licences to UK companies.

As I said originally, this is complex. We can only sell the licences to people interestes in buying them and i expect that they would be seeking long lasting licences. I don't know, of course, but it seems likely. And if the licence is even moderately long term - say ten ywars - we get back to long term investment in UK industry with no financial return.