The Association of Garda Sergeants and Inspectors says the unpaid overtime, introduced under the previous Haddington Road pay deal, should be expiring in January.
AGSI members voted against the new Lansdowne Road deal, and are also set to face a pay freeze from next July as a result.
In a statement this morning the AGSI says it has no confidence in the Lansdowne Road deal being honoured, and that it will advise members to stop taking on extra working hours from January.
