My apologies if someone has already posted this—-I haven’t seen anything here, nor an announcement by SBB. But I was checking schedules between Milano Centrale and Zurich/Luzern on the Gotthard route, and noticed that on a Sunday in mid-August EC 318 departs Milano Centrale at 13:10 and goes through the Basistunnel (which has been closed to passenger trains since an accident last summer).
Checking further, I found this train using the tunnel on every Sunday this summer. And there are similar EC trains at 15:10 and 16:10. Maybe others, but I was tired of checking.
This cuts an hour off the travel time over the Gotthard Pass route that has been used between Milan and these Swiss cities since the tunnel closure.
I thought this might be useful for people still planning summer trips that require travel between Italy and Switzerland, and are concerned about the track closure and bus link on the Domodossola route. But note that it is only on Sundays, as far as I can tell.
It is also useful for people who want to avoid the tunnel and take the scenic route. Do not automatically assume that your train from Luzern to Milan will go over the pass, at least if you are traveling on a Sunday.