Have a composite gasket on my valve covers. Check my oil regularly noticed on dip stick showing low. My right-side valve cover was leaking at the back where I could not see the leak. Tightened the cover bolts back to specks and all good now. The heating of the motor might have had an effect on the gasket like shrinking of it. Something we have to keep an eye on. It did not show a leak on the floor so figure it went out when driving. It was leaking down the back of the motor from the head and down the head gasket along the bell housing. Maybe it was showing up on the floor but thought it was the transmission seal leaking due to over filling my A833 four speed. We do have to keep an eye on these car's and watch for any leak that may happen. Glad you cought it in time.