At Red Rock, the lanes are all completely oiled before the center opens at 8 a.m., and lanes that are to be used for league play are held back from open play until the morning and noon leagues are finished. Recently on Thursdays they changed that policy for a short time, giving out league lanes for practice in the morning, but the backlash was such that I think they're back to holding them back. For evening leagues at Red Rock (and all of the Station Casinos from what I've been told) the lanes are given a 25' head run of oil about an hour before the leagues are to start. This means that fresh oil is put down on the first 25' of lane, and the rest of the lane is left with whatever is left from league and open play during the day. Considering that the open play from the afternoon may very well include a lot of kids throwing plastic balls with bumpers and the resulting criss-cross patterns of carry down, it is possible to run into some pretty scary lane conditions in night leagues.
At Gold Coast, since they now open at 9:00 a.m., the lanes are oiled before they open and may, or may not, be held back for open play before noon leagues... it all depends on who you talk to, and who you choose to believe. I'm really not sure what they do before evening leagues.
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