We are arriving on Aer Lingus from Dublin into terminal 1 and must pass through customs, on a Saturday around 1PM in October. Only carry on, no checked luggage. I understand the TGV station is in terminal 2. What is a safe cushion of time to catch the TGV?
No checked luggage is a plus, but from T1, you need the automated shuttle to the TGV station. The typical advice for people with luggage + immigration is 2.5-3 hours, and in your case I'd say somewhere closer to 2.5 hours or a hair less.
On a random Saturday in October, I am seeing a train at 2.59p and one at 4.58p.
If you are scheduled slightly before 1, I'd try for 2.59. But if it's actually, say, 1.15 or later, 4.58 feels safer.
Thank you for your advice.