Buachaill;
Pepper @6.25% looks like you had a sub-prime type mortgage.
As you say you are paying away so they have no need nor wish to reduce to circa 4.5%.
I do not know what you owe? are you in positive equity? are you in a secure job?
Call into BOI or Ulster or KBC , arrange an informal appointment with a Mortgage advisor. Given you have 6 clear years payments they will at least listen and should point you in correct direction.Do not be too disheartened if you meet a twit in any Bank, persevere , since 2% is a lot of money.
If you have good equity , good payment history, etc you are the type they want.