Originally Posted by corporate-wage-slave

It depends on the route and distance. But the downgrade reimbursement is probably 30% of base fare, see post 5 above. In which case it may be that returning the Avios difference and (e.g.) any APD saved is as good as it gets, but without more information it's difficult to say. If they are doing a full fare recalculation it may well take a few weeks, but you could do you own calculation of what you are owed, and ask them for a CEDR deadlock letter now, however it's unlikely to speed things up at this stage and they may not assist you. After 8 weeks you don't need the deadlock letter, you can go to CEDR at that point.