Hi there. We are traveling to Italy from Australia at the end of June. I'd like to book the 1010am direct train from Rome to Salerno on Thursday 30 June but the traghetti website has this message: "Seats sold out on the train 8863. Solution not saleable; Travel solution temporarily not available for the selected date". It seems to have this same message for that train service for all dates from 12 June onwards, but for dates until 11 June it is available. Does this mean perhaps that it just can't be booked until 3 weeks prior to departure? TIA.

It just means that in 2022 the summer timetable change will be on the 12th of June. It's a Sunday

ps Traghetti means ferries

No. My guess is that run has been canceled. You'll see all the other runs can be purchased . Take the departure 30 minutes earlier on 9.25am.

If it was cancelled they wouldn't show it on the official site.
The train #8863 is a Frecciabianca headed to Reggio Calabria. I.e. it's a middle-speed train subsidized either by the Calabria Region or by Rome, a train that would never break-even without public funding.

They do not sell tickets for subsidized trains when the involved body hasn't formally allocated the money, but they need to put it on the system somehow. There is only a finite number of tracks at Termini, they have put a placeholder.

Anyway, on the 12th we will discover who's right.

I would think it's just a glitch when the fares were loading. Trenitalia is known for this when summer or winter fares are loaded. If you feel you must book a ticket, Italo Treno is showing plenty of trains that day(not to be confused with an American reseller Italiarail) .

Check out italotreno as it goes from Rome to Salerno on 30 June. They also have promos and senior rates. Used them a couple of times last month while in Italy. Cheaper than trenialia for the trips I was on.

At the Trenitalia website, this train can be booked. It costs 32 EUR/pax (1st class).
ttps://www.lefrecce.it/Channels.Website.WEB/#/travellers