They were the eighth and ninth drink-drive offences for the 45-year-old, who was jailed for two-and-a-half years in the Royal Court.
Judge Russell Finch also banned him from driving for 15 years in a bid to protect the public.
Byrne, who had previously given his address as Naigy Contan, Retot, Castel, pleaded guilty to two counts of drink-driving, two of driving without insurance and two of driving while disqualified.
The 10-year driving ban was imposed on 20 September 2007 for drink-driving.
Prior to that he had 50 driving offences on his record from between 1988 and 2007. They include 10 for driving while disqualified, six for drink-driving and 13 for driving without insurance.
Full story in today's Guernsey Press
