Trenitalia-no availability to purchase April 11

I have tried to search google (in Italian) for railways on April 11, 2026, and it comes that the fast railway line between Rome and Rovezzano (that is, just south of Florence) will be closed for maintenance on April 11 and 12.

This does not mean there will be no trains; the slow line (i.e. the old one) will be still working.

But as Rome to Florence is little more than 1h30min on the fast line, and 3 hours and more on the slow line, you cannot keep the usual timetable. So basically they are not selling tickets for trains they know they cannot really run, I would expect the railway to come out with a revised timetable, probably with a reduced number of trains and much slower, and when they have the timetable they can open reservations.

Grazie Iachera.
I also did some research and when I saw there were no Italo trains available also, I figured work on the line might be affecting service. We decided to leave Rome one evening early. It doesn’t affect our trip really and our housing arrangement for Bologna could add the night.
There were not good options for the 11th either as all trains are Regionale and taking between 7-8 hours! The trains on the 12th were all posting the same price so I thought it might be because they aren’t sure yet which trains, if any, will be able to run.
We went with our best gut feeling!

Probably more just a case where schedules have not yet been released, you are over 90 days out.

I do not believe they will leave only regionale trains, but the trains they will manage to pack into the two slow tracks are going to be much slower than the usual fast trains and not as frequent. The fast tracks were built to early "Shinkansen" standards (minimum curve radius, 3 km) while the slow tracks were laid in late 19th century, to the point that the slow itinerary is 78 km longer.

I'm positive all the April 11 trains displayed as "temporarily" not available on trenitalia.com will run. They have simply postponed the sales, otherwise the site would display a "no solutions found" pop-up. Not a full schedule with the barred carts.

I am not sure what temporarily means in these day's American English, but according to Trenitalia "temporarily" still means that you have to wait and not that you have to worry.

For sure "temporarily" doesn't mean that the trains displayed with a barred cart won't run and that travellers must change plans for a journey so far in the future.

There is also no connection between the displayed prices and "sorting the options", assuming that "options" refer to the number of trains that are scheduled to run. When prices of trains running later in the year are "exactly" the same, it means that Italotreno is late and that Trenitalia hasn't decided how many discounted tickets will be available, yet. In other words, when you can see only Base fares on trenitalia.com and Italotreno is missing, those on a budget should better wait.

There has never been a 90-days window on Italian Railways.

Thank you Paul and Marco.
Paul-I have found that when it comes to the Freccia line of trains, they often are so cast in stone that they are available more than the 90 days. I try to take that into consideration. About a week ago, maybe slightly more, the trains were listed for the 11th and then, surprise, the blocked shopping carts. So it was a surprise!
Marco-even if the options do come on line, we decided it was just best to go with the known right now. Yes, I like to have reserved trains purchased early mostly to take advantage of reduced fares as we prefer to travel in business. Even some of the Friday trains had sold all reduced fare options.
We are happy with our decision as an extra day in Bologna after the hustle, bustle of Rome will do us good because the next four weeks in Bologna are a bit intense.