Surprised Belfast is on the list. Usually last to get most upgrades.
Balmoral exchange covers pretty much most of the south of the city, including plenty of places which are long lines. They probably thought long and hard about this one, I can see it being one of the most expensive to implement.
(That's with having no idea what the rest of the exchange areas look like, but if they're anything like this one the overall cost will be hooge )