I have copied the information below from a .gov.uk website.
The amount of time in which an endorsement remains on your licence depends on the type of offence committed. The date in which the endorsement starts also depends on the type of offence.
Endorsements must remain on a licence for 11 years from date of conviction if the offence is:
* drinking/drugs and driving (shown on the licence as DR10, DR20, DR30 and DR80)
* causing death by careless driving whilst under the influence of drink/drugs (shown on the licence as CD40, CD50 and CD60)
* causing death by careless driving, then failing to provide a specimen for analysis (shown on the licence as CD70)
Endorsements must remain on a licence for four years from date of conviction if the offence is:
* reckless/dangerous driving (shown on the licence as DD40, DD60 and DD80)
* offences resulting in disqualification
* disqualified from holding a full licence until a driving test has been passed
Endorsements must remain on a licence for four years from the date of offence in all other cases.