Originally Posted by
LHR/MEL/Europe FF
If you have bought this all as a single ticket you won't be able to do this on-line. Generally speaking, tickets must be used in the order of coupon sequence. If you cancel any coupon, the rest of the ticket is automatically cancelled, so skipping PEK-PVG will cancel your flight to DEL.
If you want to drop the first sector you will need to completely reissue the ticket, and pay a new fare.
+1 -- and this is not just with China Eastern but would be exactly the same with absolutely any other airline in the world. Moreover, the routing may only be changed and rebooked under the new fare without losing credit from your original ticket if your ticket is cancellable or permits change of origin/destination. Otherwise, you'll have to bite the bullet and go to PEK first to board your first segment whether you needed to or not or will lose your entire ticket.