Originally Posted by LeisureFirst

If this is anything like AirMiles (not BA Miles) then it will either book into X which is a redemption booking class not earning miles or into one of the cheaper revenue buckets which do earn miles. So it's pot luck whether you actually get BA miles.

How much would the trip have cost anyway if you'd just paid for it? That might give you some idea whether you've used your miles wisely.
I don't know how Travel Rewards work so I don't know what would be a good use of them. It might be better to ask on a board that is more expert on such things - the BA board doesn't seem the right place. People here are making all sorts of assumptions (about flexibility etc.) which may apply to BA awards but may well not apply in this case