" CPI-linked price increases to offset the cost of inflation"
So prices will be going up and as broadband is included in the CPI calculation (item 8.2/3), this increase will help to cause a ripple of increases in subsequent years...
Not sure if I believe BT subscription costs should go up in line with inflation each year, although the laugh is that finance people will present the raw monetary 'increase' in revenues as growth when after inflation it should be simply treading water or even declining (remember those cost savings, some of which should be given back to the customer in the form of below CPI price increases).