I don’t seem to find any information on industrial actions that could disturb traffic on the 20th. Could be another action in other sectors than public transport though.
Tomorrow 16th february, there’s a national strike, but even then a quite some trains seem to be available.
https://www.sncf.com/fr/greve-nationale/mouvement-social-du-16-fevrier-2023
Keep checking the “disturbances” page of SNCF, information is mostly available two days before the strike. Keep an eye on the Eurostar website too, but in general international traffic is usually much less impacted. But I don’t find any sort of information of a potential strike the 20th. Next date in the books of the union is 7th of march.
Where did you reserve your seat, via Interrail or a third party, like b-europe? Usually if your trains get cancelled you get an update of SNCF via mail.
