not sure of build date but like every new sled the dealers do not always do there job and U need to do it for them. those motor's come fully assembled and dropped in to the sled as they roll on by . if it is on 1 it is on more . in fact if I understand the story that was a pick from 1 of 2 that blew together on there maiden voyage. 1 blew and his buddy blew towing him back .
1st yr of anything U can keep em from tosters to jets I want nothing to do with being the paying tester any more
This reminds me of a funny story; in 2004 I bought a new leftover 2003 REV 800 that blew at about 150 miles. I rode it from Green Bay, WI to Wausau and was on my way back to G.B. when the motor tightened up. I let it cool down and rode it few more miles until it tightened again. I opened the oil injection can and it was dry. Turns out it did not have much oil in it when I bought it and I did not check it (dummy me).
Dumb me, luckily the Dealer warrantied the work (only one cylinder and on piston set-up) and I was back on the trail.
By the way, that sled rode so awesome from the Cats/Polaris I was riding the past few years I was sold on REV. Consequently, that sled was a pig on gas/oil, it regularly got 9 MPG and the oil to go with it.
Bear