Having removed the cistern and pan, and now having pulled off the white push fit ribbed connector between pan and pipe, I find the pipe is a fraction below floor level, so what do I need to block off the hole? I don't see any need to reinstate that WC, but would prefer to leave that option open for the future, just in case.
The rigid plastic fittings seem to be socket plugs, which are the same diameter as the pipe, so no good. Pipe is exactly 4 inches.
That leaves the ribbed rubber '110mm Soil Pipe Fitting Stop End Blanking Cap 4" ' which must be the way forward?