Which, BTW, is illegal under most sane consumer protection laws, where the full price of the contract must always be shown. No annual price, no annual contract. Simple.
At the very least, if you are showing the instalment price, you have to show the number of instalments, and the fact that it is an instalment rather than a pay-as-you-go subscription.
You could certainly argue that describing the plan as $x paid monthly is outright false, when it should be "12 monthly instalments of $x".