According to press reporting today, SNCF will be establishing an alternative route to the rail line through the Alps that has been closed off since the August landslide that closed the rail route in the Maurienne Valley (right before, I think Modane, on the Paris-Lyon-Chambery-Modane-Bardonecchia-Oulx-Turin-Milan rail route). As noted in earlier posts on this subject, the rail line isn't supposed to re-open until sometime in mid- to late-2024.
Now the SNCF is going to establish (as of January 10, 2024) a replacement "rail" route that will run as follows:
TGV from Paris Gare de Lyon to Saint-Jean-de-Maurienne France
Bus from St-Jean-de-Maurienne to Oulx, Italy
Train again from Oulx on to Turin (and Milan)
The Paris-Milan journey will thus take between 7 hours and 9.5 hours (with the full train link it used to take about 6 hours sometimes 7 hours).
Also please note: SNCF will only be running one train/bus combination each way daily (it used to run three daily in each direction).
Trenitalia, which also ran trains on this route, has for the moment not established any replacement plans for the entire route.