Yeah, it’s getting cold here in Austria. We had the first snow last weekend. But we didn‘t start heating yet.
I see you have 'em cased.
I'm one of those who believes a guitar should always be protected in its case when not in use. Even coined a slogan:
"There's only two places fit for a guitar: In its case or in your lap."
I understand folks who like to see their instrument on display and also easily grabbed at will, and granted mine are easily retrieved from the closet in my living room, but we've heard at least 3 or 4 stories here of instruments that got damaged from the most unlikely of circumstances that wouldn't have happened to a cased instrument.
And incidentally I think they also help buffer sudden humidity/temperature changes.
I figured when Guild provided a case with a guitar there was an underlying message: "Yeah, this instrument is worth protecting."
Best of luck with the new luthier! Keep us posted, we love happy endings.
Oh yes, 68% humidity
is a bit high and would have the effect of swelling the top, increasing its slight radius. It would also tend to lower the action somewhat if the fretboard extension rises more than the bridge and the neck's got excessive backbow.
Which reminds me, the truss-rod may be misadjusted, do you know how to measure the action? That might be a dead giveaway. I'll check back tomorrow.