From what I read they're different bridges. But I'm out here in Arizona, what do I know.
The New York State Thruway Authority is replacing the Tappan Zee Bridge with a new 3.1-mile state-of-the-art, twin-span bridge across the Hudson River between Rockland and Westchester counties.
About | The New NY Bridge Project
There is a reason the OP did not include a link. This happened more than a year ago and you are correct.
I hold firm opinion that it's none of my business nor concern what they name things back in New York. Wasn't going to comment at all but your original posting about lack of a link added to my suspicion which caused me to do a search, quickly determine which of the resulting links seemed most impartial and go from there.