It's different for us. Even if the lanes are dressed, the league rule that we have is that anyone can practice bowl before league, as long as it is not on the set of lanes your league uses.
For example, at a 50-lane house here in town, our league at the time took lanes 3 - 22. After the lanes are dressed, and a person from our league wanted to practice, they would have to be given (obviously, based on availability) lanes 23 and higher. They would not be allowed to practice on the lanes our league uses.
BL.