Outboard Year?

I bought a boat with a 80Hp 4 stroke Yamaha and the engine says 2001 , 5th month? The dealer tells me this engine is a 2002 ? Is this true?
Would it not be a 2001 because the month has not passed the 6th?

Thanks

[boats.net]

Whats the model number?

model #

The model # is 307717



??

Anyone ?????