Hiya mate
this my experience: I had the same blue smoke last 3-5 seconds in the cold morning, so asked around, the car looked at by someone "know" what they are doing, most of people said it's the Valve stem seals
so the engine top rebuilt --- took 1 week and £800
got the car back, it seems ok for 1 week and got the blue smoke again......
called an old firend in B'ham dealer, who told me change the PVC valve (can't remember the name something like that) cost £2, chanaged myself.
smoke is gone for good......
try the PVC valve 1st, cheap and easy to do, if it doesn't work, try something else.
Good luck mate