I believe once the first ball of the competition is thrown, you are not allowed to alter surface. That means first ball from anyone, not just yourself.
If the cleaner is approved for use any time, then you can use it anytime during competition. Usually the bottle will have a logo stating approved for any time use. If it contains polish, then same rule applies as altering surface. No polish after first ball is thrown.
It's rule 18 in the USBC rule book.
http://usbcongress.http.internapcdn....19Rulebook.pdf
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