Originally Posted by
vintagepilot
A question for the knowledgeable - in the OP's case, could he check baggage in at LHR for the YYZ leg, prior to doing the CDG shuffle?
Generally yes, so long as the OP enters "Don't know / not sure" in the number of bags question at OLCI. Then it can be put into the system at LHR the same day as the relevant travel, even if it is out of sequence, and I think even the self-service machines cope with that. However occasionally the computer says no, so it's good to have a Plan B for that scenario.