The original post, calls overflow to Eircom !
Have you checked the small print on your ESAT contract, they would have covered themselves with some legalese for this eventuality.
I think that there is a CPS or Carrier selection timeout which, if it kicks in, will result in the call being completed by Eircom beacuse ESAT can't 'take' it when requested.
The irony of course is that the call ended up in the ESAT network anyway because you were calling an ESAT no limits POP number, it was probably passed to ESAT by Eircom in Dublin.
This means that ESAT had the capacity to complete the call in Dublin but did not have the capacity in your local exchange to take the calls off Eircom there or nearby.
This can happen every now and then but 30 hours of downtime on the super duper ESAT network is ridiculous.
Does it mean that ESAT have closed some of their peering points with Eircom and slunk off quietly?
Alternatively does it mean that Eircom have unilaterally turned off
Carrier pre select , selecting ESAT, on your line without your authority...a method for acquiring customers from another carriers known as 'Slamming' in the trade.
You obviously believe that you still have a contract with ESAT to carry your calls.
Are you calling from somewhere not on the Irish Rail Network?