Modern FADEC turboprops use the FADEC to control the blade pitch. No first hand knowledge, but I'd expect Rolls to do something similar where the FADEC 'optimizes' the fan blade pitch for the specific operating conditions.
BTW, engine companies throw this sort of stuff around all the time to see 'what sticks'. Pratt started pitching the geared fan back in 1990 (for the initial 777) and it only started flying in the last few years and is still not in service. I also recall a Rolls pitch ~ 30 years ago for variable area turbine inlets. There are some dramatic potential improvements in operability and efficiency if the area of the turbine inlet can be optimized for the specific conditions - but of course putting variable geometry in the hottest part of the engine is non-trivial. Anyway, the concept is still out there but still hasn't seen the light of day.