Was in the same position a few months back, we've only just taken the Green fixed rate rate this week. I've learnt in that time that PTSB's headline rates (i.e. their lowest available rate) don't really follow ECB announcements, if anything they lead the announcements so the recent rate drop took into account the subsequent ECB rate reduction. Nor do they fall in sequence with ECB rates, with several months between the prior drop in PTSB headline rates and this last one.
In short, don't hold your breath waiting for the next drop to rapidly follow the next ECB announcement. We decided to bank our gain as had been hanging on at 4.4% SVR for long enough. I'm a tad disappointed as wanted to get down to 3% and it's a bit above that for existing customers (3.35%), but the 2% cashback and more importantly, the ability to lodge a chunk of rainy-day cash as a credit against the mortgage swung it for us.
FWIW, we went for the 5-year fix as goodness knows what chaos Trump's hare-brained schemes economic policies will have.