Then it all went wrong, noticed the oil pressure was barely off the stop when sat, hot, idling, in queue, gentle revving got it up to about 2.5 bar, which is about as high as it would go once on the move again (normally 4-4.5 bar on the move once warm and 1.5-2.5 bar at idle). I know the oil was changed on the service (I checked the dipstick for quantity and colour, both good) so pulled over gave the car a couple of minutes with the engine off and checked the dipstick, no oil
Whilst waiting for the recovery I had a think and as the car had been stationary about an hour I checked the dipstick again (I was bored by now) I now have far too much oil, probably about 1.5 litres too much (which is what I put in)
On the basis that the cheapest fix is best I have the following thoughts. The smokescreen is a direct result of overfilling with oil (although I didn't mean to) if so by what route has oil from an overfilled sump reached all 4 combustion chambers (up past the rings?) and will draining the surplus oil and replacing the plugs solve the problem.
Or, cost now increasing, has the head gasket gone (need to check for oil in water and vice versa in daylight but no sign at present) also to oil all 4 plugs through a head gasket failure strikes me as odd.
Given that oil pressure never exceeded 5 bar is it possible that oil pressure has built up in the cam cover and gone down the valve guides?
Any thoughts on the the means by which overfilling with oil results in oil being burnt in the engine would be welcome as would any suggestions to fix. If I have to strip it down and replace the head gasket valve stem oil seals etc so be it but an easy fix is clearly preferable.

