1) pay the €20k off the mortgage which would reduce it to €250k -
2) Change to the lower LTV band as long as it's a variable rate.
3) Get approved for the Green mortgage @ 2.25% over 5 years.
4) Compare the LTV rate from Avant -
If you qualify for the 5 year 1.95% rate ...
Saving from moving to Avant: .3% of €250k or €750 a year.
You will pay about €1,000 in legal fees, so it's worth doing.
If you qualify for the Avant <70% rate of 2.1%,
The saving would be .15% @€250 or €375 a year.
This would not be worth paying the €1,000 in legal fees for.
Brendan