2018 Impreza emits smoke on start-up

[larix23]

I have a 2018 Impreza with about 50,000 miles. A few months ago we noticed that the car emitted a puff of smoke when it was first started in the morning (cold engine start), but only after it had been sitting for a couple of days. We took it to the dealer and the dealer said that the smoke was condensation and nothing to worry about. Since then the problem has gotten worse. The smoke is now gray instead of white and the puffs of smoke are larger. It still only emits smoke when it is first started (cold engine start), but now it will do it even when it has not been sitting for 2 days. It doesn't emit smoke every time it is cold started but it happens frequently. The smoke dissipates very quickly. We have noticed that the dealer always overfills the oil when the oil is changed and the oil is currently overfilled. It is overfilled by about 1/4 to 1/2 quart. We're not sure what the problem is. I don't want to take it back to the dealer as they have already charged me to look at it without diagnosing a problem that can be fixed. I have owned the car for 5 years and what we are seeing now is not normal. I would appreciate any advice.