I recently took in a Loree top joint with a previously repaired crack that had been fairly stable over the few years that I've been working on it.
For whatever reason, the recent shift in weather to cold and very dry caused a massive shift in the stability of the joint and caused it to sustain a surface crack along the side of the instrument just below the 2nd / knuckle octave key. The previously repaired trill-key tone holes re-cracked and caused a leak in the inserts and a new crack formed in the G# tone hole. Weird.
The odd thing is that previously cracked joints I've encountered over the years don't typically suffer from that kind of catastrophic failure multiple times. A leak around the inserts is no biggie but a major timber shift causing a whole new set of large surface cracks isn't common. I was able to recover the seal and get it patched up again but I may be considering / monitoring this instrument as a candidate for joint replacement.