Because the usual SOP is to cancel the cabin and therefore the original booked flight with more than 2 weeks notice. They also offer a full refund and offer the traveller the CW alternative So that would work under EC261 if the flight was actually cancelled. But as I say, the Regulation just says that if that airline places you in a downgraded cabin then the reimbursement method kicks in, unfortunately from BA's perspective it doesn't matter if the passenger accepted the change in some form or other. Still, depending on the amounts involved, the reimbursement under Mennens of BA's Involuntary Refund methods may not be that spectacular, so it's best to work out an alternative First service and avoid the hassle.