Aer Lingus has said it is willing to implement a new rostering arrangement for cabin crew, but only if no costs are incurred.
Talks are continuing between management and officials from IMPACT at Dublin Airport, aimed at resolving the roster row.
A technical group is examining options to draw up a model of how a rota of five days on and three days off would work.
However Aer Lingus has said there are 37 separate requirements that need to be addressed to ensure the plan is cost neutral.