Hi, I bought tickets for 2 PM in May, including the Renoir exhibit. Now I am thinking it would be nice to eat at Cafe Campana for lunch, would they let us in earlier for lunch or let us change our time? Is the cafe worth making change? Thanks!
The café is fine if you are already in the museum. Reservations are a relatively new requirement at the Orsay, you can try to go earlier. They might let you in before 14h.
You'll have to ask them direct. Email this question to the link on their website.
The main issue is the construction around where the "old" entrance is. That's also where the information booth is, and anyone without a time entrance ticket enters on that side of the building. If you have a timed entrance you queue up on the quay side entrance at the other end of the block. There are two lines, one for entry on the hour, the other for entry on the half. They start forming up early, but don't get into line more than an hour early because there's no room.
So, if you wait to find out you'll be walking from one end of the museum to the other just to get in. The restaurant is not accessible without getting into the museum.
Have you decided what you’ll be doing that morning? If you are on the Tuileries side and the day is nice you might consider eating at one of the cafes in the garden.
I would eat before the museum. This is just based on limited experiences, 3 visits since 2019, but I think you're likely to find a long line to eat there. I haven't eaten there, but remember seeing long lines as I walk by. The reviews on google maps are pretty bad (3.5).