Changes proposed by the Boundary Commission recommend changes to the constituencies. If you live south of Guilford St you'll won't be voting in Holborn and St Pancras, you'll be in the 'Cities of London and Westminster' constituency.
The reason behind it is to try and make the constituencies all approx the same size for fairer representation. That seems ok, but HV feels little affinity with
Pundits think the changes are unlikely to be implemented. HV agrees - Parliament has quite a bit going on at the moment. However, it's far from the firs time that this change has been suggested. Who knows what'll happen in the future.