They have kept the interest rate lower than the big 4 by about 0.7 percent which is fairly significant. (
This reminds me. Our bank gives us a 0.7 discount off the standard interest rate on what they call their wealth package. It's a bit of a misnomer because you actually get it if your mortgage is $250K+ so it should be called a debt package not a wealth package

Now I think I read somewhere that most banks do this - it's pretty standard but sometimes you have to ask them as they may not have done it automatically. So if your mortgage is more than 250K and you don't already have a discounted interest rate, maybe look into it - or ask a mortgage broker.

My biggest tip, which you probably already do is to only give yourself and DH a certain amount of spending money per pay. Everything else bar household spending goes on the mortgage. The best way to reduce household spending for us is meal planning. Less visits to the supermarket, more lunches taken to work and less trips to supermarket = less stuff that we don't need.