Originally Posted by SK AAR

Sorry but this has no merits. Once confirmed by the pax LH just can't rebook the pax back - what if the new flight actually for some reason suited the pax very well? How should LH know if the pax is happy with the rebooking or prefers to be put back on the original flight? Once confirmed by the pax it is up to the pax to contact LH and request to be put back on the original flight if such opportunity arises - this should be done well in advance and not last minute at the gate. This clearly didn't happen here and the OP became aware of the reinstated flight way too late.