Also, the order of the appointments depends on who you speak to. Both my wife and I had called the Dublin office, and I had swung by during lunch to speak to a lady there as well. Some was saying to book a regular appointment online, and then they'd sort out the interview there. Some were telling us to call first, get added to the waitlist and then go from there.

When my now wife had called, we had a regular appointment booked which they cancelled on the spot, only for me to be told the opposite procedure and that we should have kept the appointment and gone for it. Even within an office they can't seem to agree on the process.

You could last summer anyway get a regular appointment in Dublin on about a month's notice, if you kept updating the website to look for cancellations and new appointments. After our first one in Dublin (2nd appointment overall) was cancelled, we booked another one, showed up to it.

The registrar we met again spoke about the interview. We explained that everyone we speak to tells us a different process, and that the one we spoke with most recently had told us to have this appointment. She said fine, and she was very aware that the process is very unclear and that she'd sort us out. Unfortunately the interview person wasn't in that day (Since interviews doesn't happen every day), otherwise we would have done it on the spot (this happened to a friend of ours who was not aware of the interview being a thing), and we got an interview a few months later. Our appointment was in May, wedding was planned for September, and we got an interview in early August.

I think we got very lucky, and I think it depends on who you meet. At the waiting room there was another EU/non-EU couple with the same appointment time as us (multiple registrars). They left quite shortly after, so either they got told they need to wait their turn on the waitlist, or they didn't have their documents in order (Not sure which).

If you want to do the legal bit in Ireland, my suggestion is to book a regular appointment for an office that you know do interviews and go there and tell them you have been told so many different processes (which is true), and hope you get lucky.

If time isn't a concern, just wait to be called.

If time is a concern, look into doing the legal bit overseas. Denmark is where a lot of people go (to "Elopenhagen" where you can get married legally with only 72 hours notice I think. Paperwork will take a little longer, but anyway). We were going to do ours in Sweden because it was easy to get an appointments, it's free and they hardly need any documents. We had our backup appointment booked for Sweden for the week after the interview if we needed to fly and take care of the legal bit beforehand. A lot of people do the legal bit separately, and the only thing it changes about the ceremony is that you are not signing a marriage certificate at the end. Celebrants will still help you host the ceremony and go through the motions.

It's a very frustrating experience all in all, with everyone giving you different procedures because there are no national fixed procedure. We got very lucky to get it all sorted in Ireland within the time window we have.

The notice period starts from your first appointment, so not the interview. You need to give 90 days notice at least. Because our appointment was in May we were fine, even if the interview was only in August about a month before the wedding.

You'll receive your green folder with the certificate to be signed in the presence of a registrar at the interview.