As per the recent announcements / emails, Plus net have changed their products.
Easystart has not been offered for some time and is not available to new customers.
Your payment is higher because you did not pay for your activation and modem up front and as such this was deferred and included in your monthly payment.
If you have completed 12 months then then ask for a downgrade to one of the newer products. You will benefit from an upgrade in speed, providing your line can support it and if and when BT upgrade your line. You will alos save some money in the long term. You will however be liable to a one off downgrade fee of £14.99.