Bus Eireann is to issue four weeks' protective notice to staff in advance of forthcoming industrial action by clerical workers at the company.
A senior SIPTU official confirmed that some staff had already received their notices and said the company was in the process of issuing notices to the remainder of its 3,500 staff.
The only exceptions are 250 clerical staff who have served strike notice on the company in a dispute over pay.
Their planned industrial action consists of the withdrawal of labour on the 25 October, which is the Friday before the Bank Holiday weekend.
It would resume on Tuesday 29 October and every Monday and Tuesday thereafter until the dispute is resolved.
