Originally Posted by Viajero
I have twice had (involuntary) stopovers in LHR when travelling on an 'x' coupon. Both times checked-in with BA after the 24hr mark for the onward flight, and on each occasion BA didn't bat an eyelid.
A big YMMV, of course.
Was this recently (within the past year?). BA used to be very free and easy about changes, using stickers freely and doing things like taking 2 flight coupons instead of a reroute (flying A-C when ticketed A-B-C) ... but all this changed a couple of years ago, and BA recently (past 12 months) has been very strict at things like this.
Perhaps you have great luck, or are very charming. My own experience is that BA agents look at it closely and catch these discrepancies every time, at least for the past year.