Just in case you haven’t seen this from the new White Paper on the Great Repeal Bill (where have you been?), here are a few paragraphs on the intended post-Brexit influence of the European Court of Justice (CJEU) on English employment law:
2.12 The Government has been clear that in leaving the EU we will bring an end to the jurisdiction of the CJEU in the UK. Once we have left the EU, the UK Parliament (and, as appropriate, the devolved legislatures) will be free to pass its own legislation.
2.13 The Great Repeal Bill will not provide any role for the CJEU in the interpretation of that new law, and the Bill will not require the domestic courts to consider the CJEU’s jurisprudence. In that way, the Bill allows the UK to take control of its own laws. We will, of course, continue to honour our international commitments and follow international law.