My 2012 29 QBH was mfg in Jan 2012, it appears that this is when the roof material was changing as I have firm orange peel (Alpha Ply) on the roof however the slide has soft/plyable smooth (EPDM) on the top. I just assumed this difference indicated what was available and the slide was built prior to the final trailer assembly.
Prior to this TT I had a 2012 26BH, mfg in May 2011, and it was EPDM roof.
I guess my point is VIN is the best determining factor, however there could be reasons why Jayco CUstomer Service could provide conflicting data.
2007 Chevy Duramax LMM/Allison
2012 Jay Flight 29QBH
2012 Jay Flight 26BH (Sold)