Which law would that be ?
Presumably The Immigration Act 2016
(Part 6 Border Security)A Lib Dem dominated statute from Cameron's 'lickspittle'
administration, that could stand editing with a Govt now 'supposedly' of a different persuasion and majority. However the faceless 'Remainers' will not support amendment and with Keir Starmer's persuasion leading the opposition, fierce objections will resound. Then it has to pass in the Lords, well stocked with Liberals, Socialists and 'Cross-bencher' stonewallers, endemically opposed to immigration control
per se. That's without the Civil Service, who will actively oppose any change, just for the sake of it.
Exiting the EU at the year end is also now very unlikely to happen considering the army of remainers presently ensconced in the
arboretum above.