GB Prices
Isn't it the case that until easyJet actually buy GB (probably sometime this week) the seats will continue to be sold by BA?
If the sale fell through then it would continue as if nothing had actually happened - hence BA are still selling biz tickets on the flights and also are still in charge of pricing. Given that BA are going to start flying some of the routes themselves after the takeover it therefore also makes sense for them to stick the prices up on the GB routes as then people will book their flights rather than GB's.
The current eJ advertising of these new routes is due to a) the sale being almost guaranteed and b) eJ having a codeshare arrangement for the summer in case it does all fall through.