Well, we got the cancelation email today - looks like it was sent out exactly one week ahead of the scheduled departure (in case it helps others, it appears the timing was quite specific, and it looks like they are canceling exactly 1 week in advance of departure times).

Email says our CDG-SEA flight is canceled (the first leg IST-CDG appears still intact). Nothing is rebooked yet (email says they’ll get to that ASAP). There’s one nonstop (AF/DL codeshare) that I’d like to be rebooked on (rather than one of many routings with multiple connections) but it seems we are at their mercy for rebooking. It appears I can’t rebook or select the rebooked flight online (have tried many ways, but we’re limited to phones and an iPad, no laptop/computer here), via browsers or the AF mobile app; that seems broken or not available. Evidently we have to call, which is problematic (we have SIMs but our plan doesn’t allow international calls, so we can’t call the US or French CS numbers). Our hotel was kind enough to try calling the AF Turkey office (presumably in Istanbul) using their phone, but we just were left on hold until after that office’s closing time. I will try that again in the morning but so far it has been frustrating.