A painting crew (who otherwise was doing a perfect job) made a goof, and before I talk to the boss, I am hoping to get an idea for how bad it is.

My old exterior wooden steps have been covered in a water-based stain over the years. A few days ago the painters put on a coat of the same product I had been using (some left-over I had). I saw them using the can, so I know it was the water-based product.

Yesterday, a different crew member said he would put a second coat on, but this morning I looked at it and realized he instead used an oil-based product for the second coat. I am guessing it is the oil-based paint they are using on the house trim, which is almost identical in color.

While it is a screw up, I don't really care as long as the product lasts. So my question... is this going to peel off in a year because of the mixing of products? Is it ok to put oil-based paint on a water based stain? Is it a problem that the wood hadn't been primed with actual primer before using an oil-based paint?

In case it matters, the water-based stain they applied in the first coat had definitely dried before they applied the oil-based paint.

Lefty