It was approved in the EGM in September so has received Shareholder approval. Details are on the IAG site under EGM 2013 here if you are interested:
http://www.iairgroup.com/phoenix.zht...p=irol-meeting
Presumably BA haven't actually signed the contract with Boeing yet but given these are not due to be delivered till 2017 and later that might not be unusual.
As you say it seems to be a formality.