Just had a conversation with the agent we use for booking our ferries from Italy to Greece. There are less discounts this year, and even if you book early there is no 'early discount' for the camping deck. (Discounts still available if you are parked elsewhere but NOT on the 'open deck'. - No good for us as we will have two dogs with us and need the open/camping deck.). I reckon the Italy to Greece route is getting more and more popular with Motorhomers, (always plenty from Germany, the Netherlands, France and Italy), so there are less offers available.
There is still a 30% discount on Internal Greek routes (providing you use the same ferry company from Italy to Greece), if anyone is travelling on from the mainland to one of the islands. It is also possible to still get an 'open ticket' at no extra cost as long as you are travelling back in the same 'price band.'
Ancona to Patras continues to be a popular route....we had to do Bari to Patras last year to get the dates we wanted, as we were late booking. If anyone is planning to do this journey in the Spring/early Summer then I'd advise them to give some serious thought to it sooner rather than later!