A "redemption figure" usually means the balance on an account which the solicitor must pay to redeem the mortgage.
If you ask NIB for a redemption figure, they will just tell you the balance on the account.
National Irish Bank is not offering such deals at the moment and are unlikely to do so in the future. Of course, that doesn't stop you from asking them, "If I sell my house and pay off the cheap tracker early,how much will you accept?" . I doubt if they would put you on a higher rate as a result, but if it's in the contract, it's a risk.