I thought after about the textures - thanks for pointing that out. I realised after that I should have said to just delete the faces and then make new ones. The operation is called spin quad or spin edge and there is a plugin for it but I don't find it any quicker.
The idea of keeping with quads is so that if you have a similar situation on a different part of the mesh and need to put the loop cut in, you know where its going. TRis get tricky at UV stage as well.