I know a lot has been said about the SES light on the dash, but for one last time any advice on my next steps re determining the cause and/or turning it off .

I just changed the oil, put on my snow tires, replaced the O2 sensors (4 of them) today and all was good until I good half way home and on came the light.
It has been serviced by the Rover dealer at every interval and now has 82,000 miles/131,000km.

Runs and sounds good.

Past posts show how to reset the light by shorting the red emmission maintenance reminder box to buying a OBDII CODE READER.
I would be very interested in DiscoMike's and/or mikemeyer0's view as they seem to have given advice before on the subject.

Derek