I suggest you book your tee time for 11:45 a.m. on maintenance days. This way when they reopen the course at 2 p.m. you will be just about finished with the first nine holes and you can then play The Back 9 which will then generally be open. Not 100% guarantee open but generally.
They alternate every week. One week the front 9 will be closed for maintenance and then next week the back 9 will be closed. You can play 9 holes on the open side or play it twice if you like.
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