Note that the above 12-month grace period will not apply to manufacturers of Class I devices and general IVDs that are currently required to register with the MHRA. 

Registration for custom-made devices will be in line with the risk class of the device. Failure to register by these dates will mean that you will no longer be able to lawfully place your device on the UK market. 

Class I devices, custom-made devices and general IVDs being placed on the Northern Ireland market must continue to register as normal as the 12-month grace period will not apply.

Disclaimer: the above is based on the current information received from various sources and from the MHRA directly. However, everything may changed or be more detailed with a new upcoming law. 

Special requirements may apply for Northern Irland.