The Ulster strategy would be something like this:
1) Most existing Ulster customer won't notice the rate change or will be unaware of the new products - vast majority of customers
2) If they notice they won't go through the hassle of changing bank - Some customers
3) If their customers notice and kick up a fuss, Ulster will let them switch to the new Ulster products - Some customers
4) Customer will walk with their feet - Tiny minority.
So they screw most of their existing customers in the hope that inertia will the driving consumer force.
It is sad that banks can play these far from transparent saving product games with their customers.