Your unit isn't old enough to have this problem but I guess if it could happen to me, it could happen to you.
I had the same problem for a year or two on my Discovery and I just lived with it until one day, there simply was no more air being produced.
No need to give you the long story. The Cummins in my Discovery has a single cylinder air pump with a 90-degree elbow at the top which connected to the hose going to the air dryer.
Somehow, that elbow had worked itself loose from the pump housing and finally just fell out. I found it by accident ... purchased a new brass elbow, installed it and built up air pressure quicker than ever before.
100k miles plus and still building plenty of air.
Guess what I'm saying is that the air pump outlet is a good place to start, then it's pretty easy to trace the lines through the air filter and on toward the front of your Winnie. If they're all tight, you might even try popping your drain valves to make sure a piece of crud isn't holding one of them open just a bit.