Assuming it's not a WT ticket then you can upgrade it, if award availability is there.

My advice, though, is to forget booking the base portion online if it's causing trouble and do the whole lot on the phone. Remember the booking has to be made with your local EC club, regardless of origin, so if you're based in Germany (eg) then call Bremen to do it.

In cases like this the offline fee is worth it just for the peace of mind.

BAH