Under the Retained EU Law (Revocation and Reform) Bill the Government originally stated that almost all EU law will be automatically revoked at the end of 2023, unless a statutory instrument is passed to preserve it.
That position has now been reversed meaning that all EU law will remain binding in the UK unless it is expressly repealed.
In relation to employment law, the list that the Government intends to revoke on the 31 December 2023 only contains two Regulations:
The Community Drivers’ Hours and Working Time (Road Tankers) (Temporary Exception) (Amendment) Regulations 2006
The Posted Workers (Enforcement of Employment Rights) Regulations 2016