A bit of smoke

I hope this is nothing but ive noticed recently when i get in the R after its been stood overnite, ill start it let it warm up, drive about 10 miles to let oil temp warm up & when i hit boost for the first time it throws abit of smoke out? it dousnt look blue or black. its looks like grey smoke in my rear view mirror!

But then it stops & dousnt do it again no matter how much i hit boost. Its only first time after its been stood overnight for example! Dous this sound like it could just be "sut / Crap" thats settled in the exhaust whilst its been stood still for a a day or 2?

Condensation?

Hmmm maybe? thought that would of cleard after around 10 miles as its not been particularly cold recently. Its looks thicker than condensation.

Im not to worryed as it stops after the first time i put my foot down, But just want to catch the problem before i braik something

Im hoping its just sut out of the exhaust whilest its been sat?

Mines exactly the same, I only drive my r on the weekends and once I do put my foot down once its warm it does throw like a puff of dust not blue or black and after that it goes away every time I hit boost.