I happen to be on UA 984 (CDG-SFO, orig 9am dep.) in a couple of hours, and overnight there have been a couple (?) of aircraft swaps as the original inbound IAD-CDG is heavily delayed and now swapped out for the SFO-CDG 772.

The interesting thing to me is that while all flight status / mobile boarding passes currently say that departure time is at 10:23am (which is implausible as inbound SFO-CDG only forecast to arrive to gate at 10:07am), the PDF boarding pass I just printed says 11:00am boarding time, which I believe.

Interesting how many systems there must be with hidden info behind the scenes...

Side note, I am thinking to sleep a little extra, but not wanting to risk the security scan barriers (if they enforce that at CDG for delayed flights). Anyway, originally this was going to be delayed by 5 hours because the inbound was IAD-CDG UA 915 (and it was odd to me that they would rotate the planes around). I guess EU penalties made them heavily rethink that. They actually sent the 5 hr delay notification during the night, but soon after retracted that, based on subbing in the SFO aircraft I guess. I don't think many people took them up on the change waiver (as it is still available) because the seat map is pretty much unchanged, and they are only offering UA IAD, EWR, ORD flights as alternatives.