Ryanair could be facing a major scheduling problem at Dublin airport after new services it is introducing were allocated slot times at between 5am and 6am.
The airline last night said discussions on the issue were "ongoing" but, at present, flights sold on its website are for later in the morning.
While Aer Lingus offers early flights from 6.15am onwards, services between 5am and 6am are among the earliest ever offered at Dublin airport.
Ryanair is hoping to introduce 50,000 extra seats to the Dublin market over the next few months. But congestion at the airport could play havoc with these plans. Airlines prefer to have as many slots as possible at peak times - usually between 7am and 9am.
Ryanair is taking legal action against the aviation regulator on the issue. It believes it is becoming impossible to add services to the airport at peak times.
For many years, the allocation of landing slots at the airport was a matter for the airlines themselves.
A few months ago, the aviation regulator handed responsibility over to a private company, Air Co-ordination Limited. Nobody from this company was available for comment last night.
An announcement from the aviation regulator is expected next week. This announcement should deal with the issue of fines for airlines who do not co-operate with their allocated slot times.
On December 21st, Ryanair announced it would be basing five new Boeing 737-800 series aircraft in Dublin.
These allow Ryanair to open up 18 new routes from Dublin to continental Europe. Frequencies are also set to increase on eight existing Dublin-Europe routes.
This additional capacity will allow the airline's traffic at Dublin to grow from 5.5 million to seven million passengers annually, as Ryanair tries to grow its general traffic to 40 million passengers per annum.