Pretty sure it is. Our 2012 which we have hopefully just sold has a lot more sealant in hinge than the 2010 we replaced it with.
We also had some leakage in a really heavy downpour with the bed end closed on the 2010. I found some mention of a factory fix of this on here when I searched it up. I have placed more sealant in the hinge end, trying to replicate the later models hinge. So far so good, but haven,t had the same amount of rain so far. A heavy hit with the hose was not enough to cause the problem again. Hoping it has fixed it as we weren't planning on a trip for a while and it was only luck that we noticed the wet mattresses.