€104 sounds normal enough for an avios TATL redemption. If you paid only 35 before then you did very well. I'm not sure if the calling BA trick still works, probably just give it a go and check is easiest. Just FYI it's not really 'taxes' that is incorporated into the cash payment on avios fares. Some of it is taxes for sure but most of it is 'surcharges' which is basically the airline just adding on extra cost to cover themselves (i.e. make more money).