Not sure where you are looking here (I mean, surely, it can't be Seatguru????) but all WTP seats, in all BA aircraft, have a full recline. You would be better off focusing on the seating guides in this forum, including the one for A350s, and you'll find them all in the BA Forum Dashboard.
There are a few WT seats on A350s (row 35) which have limited recline, but they are usually blocked off until the aircraft gets pretty full. Otherwise all longhaul seats recline on BA.
https://www.aerolopa.com/ba-type-351-seatplan
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