I thought that the offline booking fee was now being waived for any instance when the booking was simply impossible to do on BA.com.
However, the (very helpful) agent I spoke to last night in Newcastle when booking some partner awards gladly relieved me of £30 (£15 x2) as he was making the booking.
He said that the waiver only applies to the Amex 241 voucher
Anyway, I managed to redeem at over 2.8p/mile so still a bit of a bargain.