My 2015 Forester, according to the owners manual, takes 5.1 quarts of synthetic oil when the oil and filter are replaced. Do dealers install 5, 5.1 or 6 quarts and if it is 6 does that do any harm to the engine?
I don't know how anyone on the forum is going to know that.
If you put in 6 quarts and now regret it, drain some oil out, it's messy but doable. You need to be happy.
But, I'd probably drive car a few miles and check the dipstick quickly to see if there are air bubbles whipped into it; if not I'd let it go. Just me.
It probably depends upon the dealer but some on this forum have reported that dealers are overfilling engine oil, perhaps to mask oil consumption. I noticed that the service receipt from my dealer states "up to 6 quarts" for the particular code they use for pricing purposes.