If the painting is dry, I wouldn’t worry about it being tacky.
But if paint is tacky, then it isn’t dry, Don!
BTW, sometimes oil paint need six months or year to dry. The problem comes when paint isn’t dry after three years. Old masters recommended to wait “as much as possible” before varnishing and at least one year to get properly dried painting surface. Modern varnish manufacturers restricts drying time to “more than six months”. With one reason -advertisement.