Glad to hear this worked out so well for you, but my real reason for posting was that I almost gasped out loud when I read you started with about a half turn on the truss rods!
The generally recommended approach is to try something like 1/8 or 1/4 turn, and unless you know (by measuring or something) that things are really out of whack, not to go much more than about 1/4 turn per day.
But given that it's had a few days to settle and you seem very pleased with the results, it sounds like you did the right thing.
It is quite normal for an instrument to take several months, sometimes more like a year, to stabilize after construction. It may also be adjusting to your environment, if conditions are different than where it was built. But every piece of wood is different, so you never know.
Also, I don't recall whether your JPJ was purchased new or used, but in any case it could be that the neck on it was (mostly) constructed many months earlier, relative to the time you got it. Sometimes these things race through production in just a couple of months, while others sort of lounge around for a year or longer, giving you a head start on the settling process.
