Hi Mopsy,
I'm in a similar situation, I finished up today, after being on a 3 day week since last January.
If you are with your employer more than 2 years and satisfy the other criteria you should qualify for redundancy. Check out welfare.ie, citizensinformation.ie and redundancy.ie.
As far as social welfare goes I spoke to Citizens Information earlier and was told to go to my local SW office (the 'hatch' number I was given when I first submitted a claim for 2 days) and they will change my payment to fully unemployed. I have a letter from my employer sating I finished up today and will bring that with me. I should then continue to get SW payment until I have used up my days. But am hoping in the meantime to pick up some work.
I am going to the SW office tomorrow morning so will post back here afterwards.
HTH
ATgirl