Hello Tim and welcome to our community!
The Italian railway generally releases schedules six months in advance in a grouping that spans six months of travel. So, for example, we expect timetables for travel dates next spring and summer to be released in December (most likely a six-month bookable timeframe spanning January to June). So I would suggest trying your search again on ItaliaRail6 sometime in mid-December.
In addition, we try to keep our customers informed as soon as any new timetables are released by posting a notification on our Train Timetables page11 here in the community. If you go to that page and click on the blue 'Follow' box in the upper right corner, you'll get an email notification any time we post an update about schedule releases there.
Hope this helps! Have a great time planning your Italy travels and let us know if there is anything else we can help you with.