I've been down that path a few times... trying to find "the perfect bass", just because, and guess what, there isn't. It's a temptation, a never ending quest, and Talkbass doesn't help a bit. Just last night I lost a lot of sleep, because I have a couple of "opportunities" to get a "better" bass, which would require me to then sell an otherwise fine bass, and I need to make a couple of decisions quickly.
Scarcity, curiosity, information overload, FOMO (fear of missing out), and sleep deprivation, all these and many other factors influence your decision. You need to be able to recognize those in order to decide what's best for you, and live with it without regrets.
Since I'm not in your shoes, looking at the situation from a distance, and going just by the information on your post, I would not sell a great 2016 bass to get a 2008 specimen of the same bass. The difference will be negligible (but you're going to play it, and play it, and play it to try to convince yourself that is better). When our gut wants to do it, we find reasons to justify the move: a different color, less weight, the year, the pickups, country it was made, etc.
Now, what Gary said, if it is a US bass, then it is a whole different story, it is indeed a more carefully made bass, with better materials, but then it will cost 2x of the Skyline. If we're talking Skylines (and I've owned literally over a hundred of those), and you have one that you like, I'd try to find a way to enjoy it and try to ignore G.A.S.