Thank you for your replies. I really appreciate your comments.
I'm with PTSB and was on a 3 year fixed rate since the start of the mortgage. I never had a tracker and there's no mention of a tracker rate on my Letter of Offer.
I was very surprised when told they'd automatically put me on one, especially as 'new' tracker rates are now extinct. However, the margin quoted of 3.35% seemed quite high. (I haven't received anything in writing confirming I'm on a tracker or the margin/rate).
PTSB is blazing a trail in hiking their variable rates and all other lenders will follow. It seems they can charge what they like, despite Government bail-outs and guarantees.
When the ECB start changing their rates, they will go one way - upwards, for the foreseeable future. I'm probably best to stay with my 'high-margin' tracker.