The EU created this legislation, Britain nolonger has to have the archaic restrictions of this legislation with other trade agreements, which it is now able to

The EU created this legislation, Britain nolonger has to have the archaic restrictions of this legislation with other trade agreements, which it is now able to negotiate independently (an actual benefit of Brexit it can be argued). It seems logical to me the agreement between the two parties inherits from the previous relationship, it's the lowest friction option and these negotiations will be ongoing for years as the UK/EU relationship evolves.